Method by which terminal transmits uplink control information in unlicensed band, and device using method

ABSTRACT

A method by which a terminal transmits uplink control information (UCI) in an unlicensed band and a device using the method are provided. The method generates data and first UCI including information necessary to decode the data, and transmits, to a base station, the data and the first UCI through a physical uplink shared channel (PUSCH) in an unlicensed band, wherein the first UCI further includes information necessary to decode the second UCI when second UCI is transmitted to the base station together with the data and the first UCI through the PUSCH.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.17/263,774, filed on Jan. 27, 2021, which is a National Stageapplication under 35 U.S.C. § 371 of International Application No.PCT/KR2019/010081, filed on Aug. 9, 2019, which claims the benefit ofKorean Patent Application No. 10-2018-0092969 filed on Aug. 9, 2018,Korean Patent Application No. 10-2019-0003790 filed on Jan. 11, 2019 andKorean Patent Application No. 10-2019-0037173 filed on Mar. 29, 2019.The disclosures of the prior applications are incorporated by referencein their entirety.

BACKGROUND OF THE DISCLOSURE Field of the Disclosure

The present disclosure relates to wireless communication and, moreparticularly, to a method for a UE to transmit uplink controlinformation in an unlicensed band and an apparatus using the method.

Related Art

As a growing number of communication devices require highercommunication capacity, there is a need for advanced mobile broadbandcommunication as compared to existing radio access technology (RAT).Massive machine-type communication (MTC), which provides a variety ofservices anytime and anywhere by connecting a plurality of devices and aplurality of objects, is also one major issue to be considered innext-generation communication. In addition, designs for communicationsystems considering services or user equipments (UEs) sensitive toreliability and latency are under discussion. Introduction ofnext-generation RAT considering enhanced mobile broadband communication,massive MTC, and ultra-reliable and low-latency communication (URLLC) isunder discussion. In the present disclosure, for convenience ofdescription, this technology may be referred to as new RAT or new radio(NR).

Cellular communication systems, such as long-term evolution (LTE)/NRsystems, are also considering using an unlicensed band of 2.4 gigahertz(GHz), which is mainly used by an existing Wi-Fi system, or unlicensedbands of 5 GHz and 60 GHz, which are newly receiving attention, fortraffic offloading.

Basically, in an unlicensed band, since a method of performing wirelesstransmission and reception through contention between communicationnodes is assumed, each communication node is required to verify that adifferent communication node is not performing signal transmission byperforming channel sensing before transmitting a signal. Forconvenience, this operation is called a listen-before-talk (LBT) or achannel access procedure. In particular, an operation of verifyingwhether the different communication node is performing signaltransmission is defined as carrier sensing (CS), and a case where it isdetermined that the different communication node is not performingsignal transmission is defined as a clear channel assessment (CCA)having been verified.

A UE may transmit uplink data using predetermined resources without anuplink grant from a base station in an unlicensed band. In this case,since the uplink data has no corresponding uplink grant, the basestation may have difficulty in properly decoding the uplink data.Further, when the UE transmit uplink control information along with theuplink data by multiplexing (which is referred to as piggybacking), thebase station may also have difficulty in decoding the uplink controlinformation. For example, when the base station does not know which ofphysical uplink shared channel (PUSCH) resources the uplink controlinformation is mapped to and which method the uplink control informationis mapped by, the base station may have difficulty in decoding even theuplink data.

SUMMARY OF THE DISCLOSURE

An aspect of the present disclosure is to provide a method for a UE totransmit uplink control information in an unlicensed band and anapparatus using the method.

In one aspect, provided is a method for transmitting uplink controlinformation (UCI) by a user equipment (UE) in an unlicensed band. Themethod includes generating data and first UCI comprising informationneeded to decode the data and transmitting the data and the first UCI toa base station through a physical uplink shared channel (PUSCH) in theunlicensed band. Based on second UCI being transmitted along with thedata and the first UCI to the base station through the PUSCH, the firstUCI further comprises information needed to decode the second UCI.

The first UCI may comprise information on at least one of a hybridautomatic repeat request (HARQ) identity (ID) for the data, a new dataindicator (NDI) for the data, a redundancy version (RV) for the data,and a start position and an end position of a subframe for transmittingthe data.

When the second UCI is transmitted along with the data and the first UCIto the base station through the PUSCH, the first UCI may indicate atleast one of a payload size of control information comprised in thesecond UCI and information indicating a downlink slot for the controlinformation.

The second UCI may comprise acknowledgement/negative acknowledgement(ACK/NACK) information of different data received from the base station.

A resource mapped to the first UCI among resources for transmitting thePUSCH may be positioned temporally after a resource mapped to the secondUCI.

The first UCI may be mapped to a symbol right after a demodulationreference signal (DMRS) symbol for transmitting a DMRS among a pluralityof symbols forming the resources for transmitting the PUSCH, and thesecond UCI may be mapped to a symbols before the DMRS symbol.

A resource mapped to the first UCI among resources for transmitting thePUSCH may be positioned temporally before a resource mapped to thesecond UCI.

The first UCI may be mapped to a symbol right before a DMRS symbol fortransmitting a DMRS among a plurality of symbols forming the resourcesfor transmitting the PUSCH, and the second UCI may be mapped to asymbols right after the DMRS symbol.

The first UCI may be first mapped to resources among resources fortransmitting the PUSCH, and the second UCI may be mapped to remainingresources assuming that the resources mapped to the first UCI areunavailable.

In another aspect, provided is a user equipment (UE). The UE includes atransceiver to transmit and receive a radio signal and a processorcoupled with the transceiver to operate. The processor generates dataand first UCI comprising information needed to decode the data andtransmits the data and the first UCI to a base station through aphysical uplink shared channel (PUSCH) in an unlicensed band, and basedon second UCI being transmitted along with the data and the first UCI tothe base station through the PUSCH, the first UCI further comprisesinformation needed to decode the second UCI.

The first UCI may comprise information on at least one of a hybridautomatic repeat request (HARQ) identity (ID) for the data, a new dataindicator (NDI) for the data, a redundancy version (RV) for the data,and a start position and an end position of a subframe for transmittingthe data.

When the second UCI is transmitted along with the data and the first UCIto the base station through the PUSCH, the first UCI may indicate atleast one of a payload size of control information comprised in thesecond UCI and information indicating a downlink slot for the controlinformation.

The second UCI may comprise acknowledgement/negative acknowledgement(ACK/NACK) information of different data received from the base station.

A resource mapped to the first UCI among resources for transmitting thePUSCH may be positioned temporally after a resource mapped to the secondUCI.

In still another aspect, provided is a processor for a wirelesscommunication device. The processor controlling the wirelesscommunication device to: generate data and first UCI comprisinginformation needed to decode the data and transmit the data and thefirst UCI to a base station through a physical uplink shared channel(PUSCH) in an unlicensed band. Based on second UCI being transmittedalong with the data and the first UCI to the base station through thePUSCH, the first UCI further comprises information needed to decode thesecond UCI.

When uplink transmission without a grant is performed in an unlicensedband, second uplink control information may piggyback on a PUSCH fortransmitting uplink data. In this case, information needed to decode thesecond uplink control information may be additionally included in firstuplink control information including information needed to decode theuplink data. As a result, it is possible to improve performance indecoding the second uplink control information and also to improveperformance in decoding the uplink data multiplexed therewith.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a wireless communication system to which the presentdisclosure may be applied.

FIG. 2 is a diagram showing a wireless protocol architecture for a userplane.

FIG. 3 is a diagram showing a wireless protocol architecture for acontrol plane.

FIG. 4 illustrates another example of a wireless communication system towhich technical features of the present disclosure are applicable.

FIG. 5 illustrates a functional division between an NG-RAN and a 5GC.

FIG. 6 illustrates an example of a frame structure that may be appliedin NR.

FIG. 7 illustrates a slot structure.

FIG. 8 illustrates CORESET.

FIG. 9 is a diagram illustrating a difference between a related artcontrol region and the CORESET in NR.

FIG. 10 illustrates an example of a frame structure for new radio accesstechnology.

FIG. 11 is an abstract schematic diagram illustrating hybrid beamformingfrom the viewpoint of TXRUs and physical antennas.

FIG. 12 schematically illustrates a synchronization signal/PBCH(SS/PBCH) block.

FIG. 13 illustrates a method for a UE to obtain timing information.

FIG. 14 illustrates an example of a system information acquisitionprocess of a UE.

FIG. 15 illustrates a random access procedure.

FIG. 16 illustrates a power ramping counter.

FIG. 17 illustrates the concept of the threshold of an SS block in arelationship with an RACH resource.

FIG. 18 illustrates an example of a wireless communication systemsupporting an unlicensed band.

FIG. 19 illustrates a method for allocating time resources in aplurality of TTIs based on the SLIV method according to mirroringon/off.

FIG. 20 illustrates a case where a nonconsecutive CGU slot is configuredby a bitmap.

FIG. 21 illustrates a case where two consecutive CGU slots are allocatedby a bitmap.

FIG. 22 illustrates another case where two consecutive CGU slots areallocated by a bitmap.

FIG. 23 shows a method for transmitting uplink control information (UCI)by a UE in an unlicensed band according to an embodiment of the presentdisclosure.

FIG. 24 shows a specific example of applying proposed method #6.

FIG. 25 illustrates an example of CGU-UCI mapping.

FIG. 26 illustrates another example of CGU-UCI mapping.

FIG. 27 illustrates still another example of CGU-UCI mapping.

FIG. 28 is a block diagram showing components of a transmitting device(1810) and a receiving device (1820) for implementing the presentdisclosure.

FIG. 29 illustrates an example of a signal processing module structurein the transmitting device (1810).

FIG. 30 illustrates another example of the signal processing modulestructure in the transmitting device (1810).

FIG. 31 illustrates an example of a wireless communication deviceaccording to an implementation example of the present disclosure.

FIG. 32 illustrates an example of a 5G usage scenario to which thetechnical features of the present disclosure are applicable.

FIG. 33 illustrates an AI device 100.

FIG. 34 illustrates an AI server 200 according to an embodiment of thepresent disclosure.

FIG. 35 illustrates an AI system 1.

FIG. 36 illustrates an example of a parity-check matrix expressed as aprotograph.

FIG. 37 illustrates an example of an encoder structure for a polar code.

FIG. 38 schematically illustrates an example of an encoder operation ofa polar code.

FIG. 39 is a flowchart illustrating an example of performing anidle-mode DRX operation.

FIG. 40 schematically illustrates an example of an idle-mode DRXoperation.

FIG. 41 is a flowchart illustrating an example of a method forperforming a C-DRX operation.

FIG. 42 schematically illustrates an example of a C-DRX operation.

FIG. 43 schematically illustrates an example of power consumptionaccording to the state of a UE.

DESCRIPTION OF EXEMPLARY EMBODIMENTS

FIG. 1 shows a wireless communication system to which the presentdisclosure may be applied. The wireless communication system may bereferred to as an Evolved-UMTS Terrestrial Radio Access Network(E-UTRAN) or a Long Term Evolution (LTE)/LTE-A system.

The E-UTRAN includes at least one base station (BS) 20 which provides acontrol plane and a user plane to a user equipment (UE) 10. The UE 10may be fixed or mobile, and may be referred to as another terminology,such as a mobile station (MS), a user terminal (UT), a subscriberstation (SS), a mobile terminal (MT), a wireless device, etc. The BS 20is generally a fixed station that communicates with the UE 10 and may bereferred to as another terminology, such as an evolved node-B (eNB), abase transceiver system (BTS), an access point, etc.

The BSs 20 are interconnected by means of an X2 interface. The BSs 20are also connected by means of an S1 interface to an evolved packet core(EPC) 30, more specifically, to a mobility management entity (MME)through S1-MME and to a serving gateway (S-GW) through S1-U.

The EPC 30 includes an MME, an S-GW, and a packet data network-gateway(P-GW). The MME has access information of the UE or capabilityinformation of the UE, and such information is generally used formobility management of the UE. The S-GW is a gateway having an E-UTRANas an end point. The P-GW is a gateway having a PDN as an end point.

Layers of a radio interface protocol between the UE and the network canbe classified into a first layer (L1), a second layer (L2), and a thirdlayer (L3) based on the lower three layers of the open systeminterconnection (OSI) model that is well-known in the communicationsystem. Among them, a physical (PHY) layer belonging to the first layerprovides an information transfer service by using a physical channel,and a radio resource control (RRC) layer belonging to the third layerserves to control a radio resource between the UE and the network. Forthis, the RRC layer exchanges an RRC message between the UE and the BS.

FIG. 2 is a diagram showing a wireless protocol architecture for a userplane. FIG. 3 is a diagram showing a wireless protocol architecture fora control plane. The user plane is a protocol stack for user datatransmission. The control plane is a protocol stack for control signaltransmission.

Referring to FIGS. 2 and 3 , a PHY layer provides an upper layer with aninformation transfer service through a physical channel. The PHY layeris connected to a medium access control (MAC) layer which is an upperlayer of the PHY layer through a transport channel. Data is transferredbetween the MAC layer and the PHY layer through the transport channel.The transport channel is classified according to how and with whatcharacteristics data is transferred through a radio interface.

Data is moved between different PHY layers, that is, the PHY layers of atransmitter and a receiver, through a physical channel. The physicalchannel may be modulated according to an Orthogonal Frequency DivisionMultiplexing (OFDM) scheme, and use the time and frequency as radioresources.

The functions of the MAC layer include mapping between a logical channeland a transport channel and multiplexing and demultiplexing to atransport block that is provided through a physical channel on thetransport channel of a MAC Service Data Unit (SDU) that belongs to alogical channel. The MAC layer provides service to a Radio Link Control(RLC) layer through the logical channel.

The functions of the RLC layer include the concatenation, segmentation,and reassembly of an RLC SDU. In order to guarantee various types ofQuality of Service (QoS) required by a Radio Bearer (RB), the RLC layerprovides three types of operation mode: Transparent Mode™,Unacknowledged Mode (UM), and Acknowledged Mode (AM). AM RLC provideserror correction through an Automatic Repeat Request (ARQ).

The RRC layer is defined only on the control plane. The RRC layer isrelated to the configuration, reconfiguration, and release of radiobearers, and is responsible for control of logical channels, transportchannels, and PHY channels. An RB means a logical route that is providedby the first layer (PHY layer) and the second layers (MAC layer, the RLClayer, and the PDCP layer) in order to transfer data between UE and anetwork.

The function of a Packet Data Convergence Protocol (PDCP) layer on theuser plane includes the transfer of user data and header compression andciphering. The function of the PDCP layer on the user plane furtherincludes the transfer and encryption/integrity protection of controlplane data.

What an RB is configured means a process of defining the characteristicsof a wireless protocol layer and channels in order to provide specificservice and configuring each detailed parameter and operating method. AnRB can be divided into two types of a Signaling RB (SRB) and a Data RB(DRB). The SRB is used as a passage through which an RRC message istransmitted on the control plane, and the DRB is used as a passagethrough which user data is transmitted on the user plane.

If RRC connection is established between the RRC layer of UE and the RRClayer of an E-UTRAN, the UE is in the RRC connected state. If not, theUE is in the RRC idle state.

A downlink transport channel through which data is transmitted from anetwork to UE includes a broadcast channel (BCH) through which systeminformation is transmitted and a downlink shared channel (SCH) throughwhich user traffic or control messages are transmitted. Traffic or acontrol message for downlink multicast or broadcast service may betransmitted through the downlink SCH, or may be transmitted through anadditional downlink multicast channel (MCH). Meanwhile, an uplinktransport channel through which data is transmitted from UE to a networkincludes a random access channel (RACH) through which an initial controlmessage is transmitted and an uplink shared channel (SCH) through whichuser traffic or control messages are transmitted.

Logical channels that are placed over the transport channel and that aremapped to the transport channel include a broadcast control channel(BCCH), a paging control channel (PCCH), a common control channel(CCCH), a multicast control channel (MCCH), and a multicast trafficchannel (MTCH).

The physical channel includes several OFDM symbols in the time domainand several subcarriers in the frequency domain. One subframe includes aplurality of OFDM symbols in the time domain. An RB is a resourcesallocation unit, and includes a plurality of OFDM symbols and aplurality of subcarriers. Furthermore, each subframe may use specificsubcarriers of specific OFDM symbols (e.g., the first OFDM symbol) ofthe corresponding subframe for a physical downlink control channel(PDCCH), that is, an L1/L2 control channel. A Transmission Time Interval(TTI) is a unit time for subframe transmission.

Hereinafter, a new radio access technology (new RAT, NR) will bedescribed.

As more and more communication devices require more communicationcapacity, there is a need for improved mobile broadband communicationover existing radio access technology. Also, massive machine typecommunications (MTC), which provides various services by connecting manydevices and objects, is one of the major issues to be considered in thenext generation communication. In addition, communication system designconsidering reliability/latency sensitive service/UE is being discussed.The introduction of next generation radio access technology consideringenhanced mobile broadband communication (eMBB), massive MTC (mMTC),ultrareliable and low latency communication (URLLC) is discussed. Thisnew technology may be called new radio access technology (new RAT or NR)in the present disclosure for convenience.

FIG. 4 illustrates another example of a wireless communication system towhich technical features of the present disclosure are applicable.

Specifically, FIG. 4 shows system architecture based on a 5G new radioaccess technology (NR) system. Entities used in the 5G NR system(hereinafter, simply referred to as “NR”) may absorb some or allfunctions of the entities (e.g., the eNB, the MME, and the S-GW)introduced in FIG. 1 . The entities used in the NR system may beidentified by terms with “NG” to be distinguished from LTE entities.

Referring to FIG. 4 , the wireless communication system includes atleast one UE 11, a next-generation RAN (NG-RAN), and a 5G core network(5GC). The NG-RAN includes at least one NG-RAN node. The NG-RAN node isan entity corresponding to the BS 20 illustrated in FIG. 1 . The NG-RANnode includes at least one gNB 21 and/or at least one ng-eNB 22. The gNB21 provides an end point of NR control-plane and user-plane protocols tothe UE 11. The ng-eNB 22 provides an end point of E-UTRA user-plane andcontrol-plane protocols to the UE 11.

The 5GC includes an access and mobility management function (AMF), auser plane function (UPF), and a session management function (SMF). TheAMF hosts functions of NAS security and idle-state mobility processing.The AMF is an entity that includes the functions of a conventional MME.The UPF hosts functions of mobility anchoring function and protocol dataunit (PDU) processing. The UPF is an entity that includes the functionsof a conventional S-GW. The SMF hosts functions of UE IP addressallocation and PDU session control.

The gNB and the ng-eNB are connected to each other via an Xn interface.The gNB and the ng-eNB are also connected to the 5GC through an NGinterface. Specifically, the gNB and the ng-eNB are connected to the AMFthrough an NG-C interface, and to the UPF through an NG-U interface.

FIG. 5 illustrates a functional division between an NG-RAN and a 5GC.

Referring to FIG. 5 , the gNB may provide functions such as aninter-cell radio resource management (Inter Cell RRM), radio bearermanagement (RB control), connection mobility control, radio admissioncontrol, measurement configuration & provision, dynamic resourceallocation, and the like. The AMF may provide functions such as NASsecurity, idle state mobility handling, and so on. The UPF may providefunctions such as mobility anchoring, PDU processing, and the like. TheSMF may provide functions such as UE IP address assignment, PDU sessioncontrol, and so on.

FIG. 6 illustrates an example of a frame structure that may be appliedin NR.

Referring to FIG. 6 , a frame may be composed of 10 milliseconds (ms)and include 10 subframes each composed of 1 ms.

One or a plurality of slots may be included in a subframe according tosubcarrier spacings.

The following table 1 illustrates a subcarrier spacing configuration μ.

TABLE 1 μ Δf = 2^(μ) · 15 [kHz] Cyclic prefix 0 15 Normal 1 30 Normal 260 Normal Extended 3 120 Normal 4 240 Normal

The following table 2 illustrates the number of slots in a frame(N^(frame,μ) _(slot)), the number of slots in a subframe (N^(subframe,μ)_(slot)), the number of symbols in a slot (N^(slot) _(symb)), and thelike, according to subcarrier spacing configurations μ.

TABLE 2 μ N_(symb) ^(slot) N_(slot) ^(frame,μ) N_(slot) ^(subframe,μ) 014 10 1 1 14 20 2 2 14 40 4 3 14 80 8 4 14 160 16

FIG. 7 illustrates a slot structure.

Referring to FIG. 7 , a slot includes a plurality of symbols in the timedomain. For example, when a normal CP is used, one slot may include 14symbols; when an extended CP is used, one slot may include 12 symbols.Alternatively, when a normal CP is used, one slot may include 7 symbols;when an extended CP is used, one slot may include 6 symbols.

A carrier includes a plurality of subcarriers in the frequency domain. Aresource block (RB) may be defined as a plurality of (e.g., 12)contiguous subcarriers in the frequency domain. A bandwidth part (BWP)may be defined as a plurality of contiguous (P)RBs in the frequencydomain and may correspond to one numerology (e.g., SCS, CP length, orthe like). A carrier may include up to N (e.g., 5) BWPs. Datacommunication may be performed through an activated BWP. Each element ina resource grid may be referred to as a resource element (RE) and may bemapped to one complex symbol.

A physical downlink control channel (PDCCH) may include one or morecontrol channel elements (CCEs) as illustrated in the following table 3.

TABLE 3 Aggregation level Number of CCEs 1 1 2 2 4 4 8 8 16 16

That is, the PDCCH may be transmitted through a resource including 1, 2,4, 8, or 16 CCEs. Here, the CCE includes six resource element groups(REGs), and one REG includes one resource block in a frequency domainand one orthogonal frequency division multiplexing (OFDM) symbol in atime domain.

Meanwhile, in a future wireless communication system, a new unit calleda control resource set (CORESET) may be introduced. The terminal mayreceive the PDCCH in the CORESET.

FIG. 8 illustrates CORESET.

Referring to FIG. 8 , the CORESET includes N^(CORESET) _(RB) number ofresource blocks in the frequency domain, and N^(CORESET) _(symb)∈{1, 2,3} number of symbols in the time domain. N^(CORESET) _(RB) andN^(CORESET) _(symb) may be provided by a base station via higher layersignaling. As illustrated in FIG. 8 , a plurality of CCEs (or REGs) maybe included in the CORESET.

The UE may attempt to detect a PDCCH in units of 1, 2, 4, 8, or 16 CCEsin the CORESET. One or a plurality of CCEs in which PDCCH detection maybe attempted may be referred to as PDCCH candidates.

A plurality of CORESETs may be configured for the terminal.

FIG. 9 is a diagram illustrating a difference between a related artcontrol region and the CORESET in NR.

Referring to FIG. 9 , a control region 300 in the related art wirelesscommunication system (e.g., LTE/LTE-A) is configured over the entiresystem band used by a base station (BS). All the terminals, excludingsome (e.g., eMTC/NB-IoT terminal) supporting only a narrow band, must beable to receive wireless signals of the entire system band of the BS inorder to properly receive/decode control information transmitted by theBS.

On the other hand, in NR, CORESET described above was introduced.CORESETs 301, 302, and 303 are radio resources for control informationto be received by the terminal and may use only a portion, rather thanthe entirety of the system bandwidth. The BS may allocate the CORESET toeach UE and may transmit control information through the allocatedCORESET. For example, in FIG. 9 , a first CORESET 301 may be allocatedto UE 1, a second CORESET 302 may be allocated to UE 2, and a thirdCORESET 303 may be allocated to UE 3. In the NR, the terminal mayreceive control information from the BS, without necessarily receivingthe entire system band.

The CORESET may include a UE-specific CORESET for transmittingUE-specific control information and a common CORESET for transmittingcontrol information common to all UEs.

Meanwhile, NR may require high reliability according to applications. Insuch a situation, a target block error rate (BLER) for downlink controlinformation (DCI) transmitted through a downlink control channel (e.g.,physical downlink control channel (PDCCH)) may remarkably decreasecompared to those of conventional technologies. As an example of amethod for satisfying requirement that requires high reliability,content included in DCI can be reduced and/or the amount of resourcesused for DCI transmission can be increased. Here, resources can includeat least one of resources in the time domain, resources in the frequencydomain, resources in the code domain and resources in the spatialdomain.

In NR, the following technologies/features can be applied.

<Self-Contained Subframe Structure>

FIG. 10 illustrates an example of a frame structure for new radio accesstechnology.

In NR, a structure in which a control channel and a data channel aretime-division-multiplexed within one TTI, as shown in FIG. 10 , can beconsidered as a frame structure in order to minimize latency.

In FIG. 10 , a shaded region represents a downlink control region and ablack region represents an uplink control region. The remaining regionmay be used for downlink (DL) data transmission or uplink (UL) datatransmission. This structure is characterized in that DL transmissionand UL transmission are sequentially performed within one subframe andthus DL data can be transmitted and UL ACK/NACK can be received withinthe subframe. Consequently, a time required from occurrence of a datatransmission error to data retransmission is reduced, thereby minimizinglatency in final data transmission.

In this data and control TDMed subframe structure, a time gap for a basestation and a terminal to switch from a transmission mode to a receptionmode or from the reception mode to the transmission mode may berequired. To this end, some OFDM symbols at a time when DL switches toUL may be set to a guard period (GP) in the self-contained subframestructure.

<Analog Beamforming #1>

Wavelengths are shortened in millimeter wave (mmW) and thus a largenumber of antenna elements can be installed in the same area. That is,the wavelength is 1 cm at 30 GHz and thus a total of 100 antennaelements can be installed in the form of a 2-dimensional array at aninterval of 0.5 lambda (wavelength) in a panel of 5×5 cm. Accordingly,it is possible to increase a beamforming (BF) gain using a large numberof antenna elements to increase coverage or improve throughput in mmW.

In this case, if a transceiver unit (TXRU) is provided to adjusttransmission power and phase per antenna element, independentbeamforming per frequency resource can be performed. However,installation of TXRUs for all of about 100 antenna elements decreaseseffectiveness in terms of cost. Accordingly, a method of mapping a largenumber of antenna elements to one TXRU and controlling a beam directionusing an analog phase shifter is considered. Such analog beamforming canform only one beam direction in all bands and thus cannot providefrequency selective beamforming.

Hybrid beamforming (BF) having a number B of TXRUs which is smaller thanQ antenna elements can be considered as an intermediate form of digitalBF and analog BF. In this case, the number of directions of beams whichcan be simultaneously transmitted are limited to B although it dependson a method of connecting the B TXRUs and the Q antenna elements.

<Analog Beamforming #2>

When a plurality of antennas is used in NR, hybrid beamforming which isa combination of digital beamforming and analog beamforming is emerging.Here, in analog beamforming (or RF beamforming) an RF end performsprecoding (or combining) and thus it is possible to achieve theperformance similar to digital beamforming while reducing the number ofRF chains and the number of D/A (or A/D) converters. For convenience,the hybrid beamforming structure may be represented by N TXRUs and Mphysical antennas. Then, the digital beamforming for the L data layersto be transmitted at the transmitting end may be represented by an N byL matrix, and the converted N digital signals are converted into analogsignals via TXRUs, and analog beamforming represented by an M by Nmatrix is applied.

FIG. 11 is an abstract schematic diagram illustrating hybrid beamformingfrom the viewpoint of TXRUs and physical antennas.

In FIG. 11 , the number of digital beams is L and the number of analogbeams is N. Further, in the NR system, by designing the base station tochange the analog beamforming in units of symbols, it is considered tosupport more efficient beamforming for a terminal located in a specificarea. Furthermore, when defining N TXRUs and M RF antennas as oneantenna panel in FIG. 11 , it is considered to introduce a plurality ofantenna panels to which independent hybrid beamforming is applicable inthe NR system.

When a base station uses a plurality of analog beams as described above,analog beams suitable to receive signals may be different for terminalsand thus a beam sweeping operation of sweeping a plurality of analogbeams to be applied by a base station per symbol in a specific subframe(SF) for at least a synchronization signal, system information andpaging such that all terminals can have reception opportunities isconsidered.

FIG. 12 schematically illustrates a synchronization signal/PBCH(SS/PBCH) block.

Referring to FIG. 12 , an SS/PBCH block may include a PSS and an SSS,each of which occupies one symbol and 127 subcarriers, and a PBCH, whichspans three OFDM symbols and 240 subcarriers where one symbol mayinclude an unoccupied portion in the middle reserved for the SSS. Theperiodicity of the SS/PBCH block may be configured by a network, and atime position for transmitting the SS/PBCH block may be determined onthe basis of subcarrier spacing.

Polar coding may be used for the PBCH. A UE may assume band-specificsubcarrier spacing for the SS/PBCH block as long as a network does notconfigure the UE to assume different subcarrier spacings.

The PBCH symbols carry frequency-multiplexed DMRS thereof. QPSK may beused for the PBCH. 1008 unique physical-layer cell IDs may be assigned.

Regarding a half frame having SS/PBCH blocks, the indexes of firstsymbols of candidate SS/PBCH blocks are determined according to thesubcarrier spacing of SS/PBCH blocks described blow.

Case A—Subcarrier spacing of 15 kHz: The first symbols of the candidateSS/PBCH blocks have an index represented by {2, 8}+14*n where n=0, 1 fora carrier frequency of 3 GHz or less and n=0, 1, 2, 3 for a carrierfrequency which is greater than 3 GHz and is less than or equal to 6GHz.

Case B—Subcarrier spacing of 30 kHz: The first symbols of the candidateSS/PBCH blocks have an index represented by {4, 8, 16, 20}+28*n wheren=0 for a carrier frequency of 3 GHz or less and n=0, 1 for a carrierfrequency which is greater than 3 GHz and is less than or equal to 6GHz.

Case C—Subcarrier spacing of 30 kHz: The first symbols of the candidateSS/PBCH blocks have an index represented by {2, 8}+14*n where n=0, 1 fora carrier frequency of 3 GHz or less and n=0, 1, 2, 3 for a carrierfrequency which is greater than 3 GHz and is less than or equal to 6GHz.

Case D—Subcarrier spacing of 120 kHz: The first symbols of the candidateSS/PBCH blocks have an index represented by {4, 8, 16, 20}+28*n wheren=0, 1, 2, 3, 5, 6, 7, 8, 10, 11, 12, 13, 15, 16, 17, 18 for a carrierfrequency greater than 6 GHz.

Case E—Subcarrier spacing of 240 kHz: The first symbols of the candidateSS/PBCH blocks have an index represented by {8, 12, 16, 20, 32, 36, 40,44}+56*n where n=0, 1, 2, 3, 5, 6, 7, 8 for a carrier frequency greaterthan 6 GHz.

The candidate SS/PBCH blocks in the half frame are indexed in ascendingorder from 0 to L−1 on the time axis. The UE needs to determine two LSBsfor L=4 of the SS/PBCH block index per half frame and three LSBs for L>4from one-to-one mapping with the index of a DM-RS sequence transmittedin the PBCH. For L=64, the UE needs to determine three MSBs of theSS/PBCH block index per half frame by PBCH payload bits.

The indexes of SS/PBCH blocks in which the UE cannot receive othersignals or channels in REs overlapping with REs corresponding to theSS/PBCH blocks may be set via a higher-layer parameter‘SSB-transmitted-SIB1’. Further, the indexes of SS/PBCH blocks perserving cell in which the UE cannot receive other signals or channels inREs overlapping with REs corresponding to the SS/PBCH blocks may be setvia a higher-layer parameter ‘SSB-transmitted’. The setting via‘SSB-transmitted’ may override the setting via ‘SSB-transmitted-SIB1’.The periodicity of a half frame for reception of SS/PBCH blocks perserving cell may be set via a higher-layer parameter‘SSB-periodicityServingCell’. When the UE does not receive the settingof the periodicity of the half frame for the reception of the SS/PBCHblocks, the UE needs to assume the periodicity of the half frame. The UEmay assume that the periodicity is the same for all SS/PBCH blocks in aserving cell.

FIG. 13 illustrates a method for a UE to obtain timing information.

First, a UE may obtain six-bit SFN information through a masterinformation block (MIB) received in a PBCH. Further, the UE may obtain afour-bit SFN in a PBCH transport block.

Second, the UE may obtain a one-bit half frame indicator as part of aPBCH payload. In less than 3 GHz, the half frame indicator may beimplicitly signaled as part of a PBCH DMRS for Lmax=4.

Finally, the UE may obtain an SS/PBCH block index by a DMRS sequence andthe PBCH payload. That is, the UE may obtain three bits of LSB of the SSblock index by the DMRS sequence for a period of 5 ms. Also, three bitsof MSB of timing information are explicitly carried in the PBCH payload(for more than 6 GHz).

In initial cell selection, the UE may assume that a half frame havingSS/PBCH blocks occurs with a periodicity of two frames. Upon detectingan SS/PBCH block, when k_(SSB)≤23 for FR1 and k_(SSB)≤11 for FR2, the UEdetermines that a control resource set for a Type0-PDCCH common searchspace exists. When k_(SSB)>23 for FR1 and k_(SSB)>11 for FR2, the UEdetermines that there is no control resource set for the Type0-PDCCHcommon search space.

For a serving cell in which SS/PBCH blocks are not transmitted, the UEobtains time and frequency synchronization of the serving cell based onreception of SS/PBCH blocks on a PCell or PSCell of a cell group for theserving cell.

Hereinafter, acquisition of system information will be described.

System information (SI) is divided into a master information block (MIB)and a plurality of system information blocks (SIBs) where:

-   -   the MIB is transmitted always on a BCH according to a period of        40 ms, is repeated within 80 ms, and includes parameters        necessary to obtain system information block type1 (SIB1) from a        cell;    -   SIB1 is periodically and repeatedly transmitted on a DL-SCH.        SIB1 includes information on availability and scheduling (e.g.,        periodicity or SI window size) of other SIBs. Further, SIB1        indicates whether the SIBs (i.e., the other SIBs) are        periodically broadcast or are provided by request. When the        other SIBs are provided by request, SIB1 includes information        for a UE to request SI;    -   SIBs other than SIB1 are carried via system information (SI)        messages transmitted on the DL-SCH. Each SI message is        transmitted within a time-domain window (referred to as an SI        window) periodically occurring;    -   For a PSCell and SCells, an RAN provides required SI by        dedicated signaling. Nevertheless, a UE needs to acquire an MIB        of the PSCell in order to obtain the SFN timing of a SCH (which        may be different from an MCG). When relevant SI for a SCell is        changed, the RAN releases and adds the related SCell. For the        PSCell, SI can be changed only by reconfiguration with        synchronization (sync).

FIG. 14 illustrates an example of a system information acquisitionprocess of a UE.

Referring to FIG. 14 , the UE may receive an MIB from a network and maythen receive SIB1. Subsequently, the UE may transmit a systeminformation request to the network and may receive a system informationmessage from the network in response.

The UE may apply a system information acquisition procedure foracquiring access stratum (AS) and non-access stratum (NAS) information.

In RRC_IDLE and RRC_INACTIVE states, the UE needs to ensure validversions of (at least) the MIB, SIB1, and system information block typeX (according to relevant RAT support for mobility controlled by the UE).

In an RRC_CONNECTED state, the UE needs to ensure valid versions of theMIB, SIB1, and system information block type X (according to mobilitysupport for relevant RAT).

The UE needs to store relevant SI obtained from a currentlycamping/serving cell. The version of the SI obtained and stored by theUE is valid only for a certain period of time. The UE may use thisversion of the stored SI, for example, after cell reselection, afterreturn from out of coverage, or after indication of a system informationchange.

Hereinafter, random access will be described.

A UE's random access procedure may be summarized in Table 4.

TABLE 4 Type of signal Operation/obtained information Step 1 UplinkPRACH To obtain initial beam preamble Random election of RA-preamble IDStep 2 Random access Timing alignment information response on DL-RA-preamble ID SCH Initial uplink grant, temporary C-RNTI Step 3 Uplinktransmission RRC connection request on UL-SCH UE identifier Step 4Downlink contention C-RNTI on PDCCH for initial access resolution C-RNTIon PDCCH for RRC_CONNECTED UE

FIG. 15 illustrates a random access procedure.

Referring to FIG. 15 , first, a UE may transmit a PRACH preamble as Msg1 of the random access procedure via an uplink.

Two random access preamble sequences having different lengths aresupported. A long sequence having a length of 839 is applied to asubcarrier spacing of 1.25 kHz and 5 kHz, and a short sequence having alength of 139 is applied to a subcarrier spacing of 15 kHz, 30 kHz, 60kHz, and 120 kHz. The long sequence supports an unrestricted set andrestricted sets of type A and type B, while the short sequence maysupport only an unrestricted set.

A plurality of RACH preamble formats is defined by one or more RACH OFDMsymbols, different cyclic prefixes (CPs), and a guard time. A PRACHpreamble setting to be used is provided to the UE as system information.

When there is no response to Msg1, the UE may retransmit thepower-ramped PRACH preamble within a specified number of times. The UEcalculates PRACH transmission power for retransmission of the preamblebased on the most recent estimated path loss and a power rampingcounter. When the UE performs beam switching, the power ramping counterdoes not change.

FIG. 16 illustrates a power ramping counter.

A UE may perform power ramping for retransmission of a random accesspreamble based on a power ramping counter. Here, as described above,when the UE performs beam switching in PRACH retransmission, the powerramping counter does not change.

Referring to FIG. 16 , when the UE retransmits the random accesspreamble for the same beam, the UE increases the power ramping counterby 1, for example, the power ramping counter is increased from 1 to 2and from 3 to 4. However, when the beam is changed, the power rampingcounter does not change in PRACH retransmission.

FIG. 17 illustrates the concept of the threshold of an SS block in arelationship with an RACH resource.

A UE knows the relationship between SS blocks and RACH resources throughsystem information. The threshold of an SS block in a relationship withan RACH resource is based on RSRP and a network configuration.Transmission or retransmission of a RACH preamble is based on an SSblock satisfying the threshold. Therefore, in the example of FIG. 17 ,since SS block m exceeds the threshold of received power, the RACHpreamble is transmitted or retransmitted based on SS block m.

Subsequently, when the UE receives a random access response on a DL-SCH,the DL-SCH may provide timing alignment information, an RA-preamble ID,an initial uplink grant, and a temporary C-RNTI.

Based on the information, the UE may perform uplink transmission of Msg3of the random access procedure on a UL-SCH. Msg3 may include an RRCconnection request and a UE identifier.

In response, a network may transmit Msg4, which can be considered as acontention resolution message, via a downlink. Upon receiving thismessage, the UE can enter the RRC-connected state.

<Bandwidth Part (BWP)>

In the NR system, a maximum of 400 MHz can be supported per componentcarrier (CC). If a UE operating in such a wideband CC operates with RFfor all CCs turn on all the time, UE battery consumption may increase.Otherwise, considering use cases operating in one wideband CC (e.g.,eMBB, URLLC, mMTC, etc.), different numerologies (e.g., subcarrierspacings (SCSs)) can be supported for different frequency bands in theCC. Otherwise, UEs may have different capabilities for a maximumbandwidth. In consideration of this, an eNB may instruct a UE to operateonly in a part of the entire bandwidth of a wideband CC, and the part ofthe bandwidth is defined as a bandwidth part (BWP) for convenience. ABWP can be composed of resource blocks (RBs) consecutive on thefrequency axis and can correspond to one numerology (e.g., a subcarrierspacing, a cyclic prefix (CP) length, a slot/mini-slot duration, or thelike).

Further, the eNB can configure a plurality of BWPs for a UE even withinone CC. For example, a BWP occupying a relatively small frequency domaincan be set in a PDCCH monitoring slot and a PDSCH indicated by a PDCCHcan be scheduled on a BWP wider than the BWP. When UEs converge on aspecific BWP, some UEs may be set to other BWPs for load balancing.Otherwise, BWPs on both sides of a bandwidth other than some spectra atthe center of the bandwidth may be configured in the same slot inconsideration of frequency domain inter-cell interference cancellationbetween neighbor cells. That is, the eNB can configure at least oneDL/UL BWP for a UE associated with(=related with) a wideband CC andactivate at least one of DL/UL BWPs configured at a specific time(through L1 signaling or MAC CE or RRC signaling), and switching toother configured DL/UL BWPs may be indicated (through L1 signaling orMAC CE or RRC signaling) or switching to a determined DL/UL BWP mayoccur when a timer value expires on the basis of a timer. Here, anactivated DL/UL BWP is defined as an active DL/UL BWP. However, a UE maynot receive a configuration for a DL/UL BWP when the UE is in an initialaccess procedure or RRC connection is not set up. In such a situation, aDL/UL BWP assumed by the UE is defined as an initial active DL/UL BWP.

Hereinafter, a channel access procedure according to licensed-assistedaccess (LAA) will be described. Here, LAA may refer to a method ofperforming data transmission and reception in an unlicensed band incombination with an unlicensed band (e.g., a Wi-Fi band). Here, a cellaccessed by a UE in the unlicensed band may be referred to as a USCell(or LAA SCell), and a cell accessed by the UE in the licensed band maybe referred to as a PCell.

First, a downlink channel access procedure will be described.

An eNB operating with LAA SCell(s) needs to perform the followingchannel access procedure to access channels on which transmission(s) ofLSS SCell(s) are performed.

Hereinafter, a channel access procedure for transmission(s) including aPDSCH/PDCCH/EPDCCH will be described.

When a channel in an idle state is sensed first for a slot duration of adefer duration T_(d) and a counter N is 0 in step 4, the eNB can performtransmission including PDSCH/PDCCH/EPDCCH on a carrier on whichtransmission(s) of LAA SCell(s) are performed. The counter N is adjustedby sensing a channel additional slot duration(s) according to the stepsbelow.

1) N is set to N=N_(init). Here, N_(init) is an arbitrary numberuniformly distributed between 0 and CW_(p). Then, the procedure proceedsto step 4.

2) If N>0 and the eNB selects decreasing of the counter, N=N−1 is set.

3) When a channel with respect to an additional slot duration is sensedand the additional slot duration is idle, the procedure proceeds to step4. If not, the procedure proceeds to step 5.

4) The procedure ends if N=0 and proceeds to step 2 if not.

5) The channel is sensed until a busy slot is detected within theadditional defer duration T_(d) or all slots of the additional deferduration T_(d) are sensed as being idle.

6) If it is sensed that the channel is idle in all slot durations of theadditional defer duration T_(d), the procedure proceeds to step 4. Ifnot, the procedure proceeds to step 5.

When the eNB has not perform transmission including PDSCH/PDCCH/EPDCCHon a carrier on which transmission(s) of LAA SCell(s) are performedafter step 4 of the procedure, if the eNB is ready to transmit thePDSCH/PDCCH/EPDCCH, the eNB can perform transmission includingPDSCH/PDCCH/EPDCCH on the carrier when it is sensed that the channel isidle in at least a slot duration T_(sl) and the channel is idle in allslot durations of the defer duration T_(d) immediately before thetransmission. When the eNB senses that the channel is not idle in theslot duration T_(sl) or senses that the channel is not idle in arbitraryslot durations of the defer duration T_(d) immediately before intendedtransmission when the eNB initially senses the channel after the eNB isready to perform transmission, the eNB senses that the channel is idlein slot durations of the defer duration T_(d) and then proceeds to step1.

The defer duration T_(d) is configured as a duration of T_(f)=16 μsimmediately after consecutive slot durations m_(p). Here, each slotduration is T_(sl)=9 μs and T_(f) includes an idle slot duration T_(sl)at the start point of T_(f).

The slot duration T_(sl) is considered to be idle when the eNB sensesthe channel for the slot duration and power detected at least for 4 usby the eNB in the slot duration is lower than an energy detectionthreshold X_(Thresh). Otherwise, the slot duration T_(sl) is consideredto be busy.

CW_(p) (CW_(min,p)≤CW_(p)≤CW_(max,p)) is a contention window.Application of CW_(p) will be described in a contention windowapplication procedure.

CW_(min,p) and CW_(max,p) are selected before step 1 of the foregoingprocedure.

As illustrated in Table 3, m_(p), CW_(min,p), and CW_(max,p) are basedon a channel access priority class related to eNB transmission.

Adjustment of X_(Thresh) will be described in an energy detectionthreshold adaptation procedure.

If N>0 in the aforementioned procedure, when the eNB transmits adiscovery signal that does not include a PDSCH/PDCCH/EPDCCH, the eNBshould not reduce N in slot duration(s) overlapping with discoverysignal transmission.

The eNB should not perform continuous transmission on a carrier on whichtransmission(s) of LAA SCell(s) are performed for a duration thatexceeds T_(mcot,p) given in Table 3.

If absence of other technologies sharing carriers can be ensured in thelong term (for example, according to a level of regulation) for p=3 andp=4, T_(mcot,p)=10 ms. If not, T_(mcot,p)=8 ms.

Table 5 shows a channel access priority class.

TABLE 5 Channel access priority Permitted class (p) m_(p) CW_(min,p)CW_(max,p) T_(mcot,p) CW_(p) size 1 1  3   7 2 ms {3, 7} 2 1  7  15 3 ms{7, 15} 3 3 15  63 8 or 10 ms {15, 31, 63} 4 7 15 1023 8 or 10 ms {15,31, 63, 127, 255, 511, 1023}

Hereinafter, a channel access procedure for transmissions includingdiscovery signal transmission(s) without a PDSCH will be described.

An eNB can transmit a discovery signal without a PDSCH on a carrier onwhich transmission(s) of LAA SCell(s) are performed if a transmissionduration is less than 1 ms immediately after sensing that a channel isidle for at least a sensing interval of T_(drs)=25 μs. T_(drs) isconfigured as T_(f)=16 s immediately after one slot duration T_(sl)=9 sand T_(f) includes the idle slot duration T_(sl) at the start point ofT_(f). If it is sensed that the channel is idle for slot durations ofT_(dars), the channel is considered to be idle for T_(drs).

Hereinafter, a contention window adjustment procedure will be described.

When an eNB performs transmissions including a PDSCH related to channelaccess priority class p on a carrier, the eNB maintains a contentionwindow value CW_(p), and adjusts CW_(p) for transmissions using thefollowing steps before step 1 of the foregoing procedure.

1) For all priority classes p∈{1, 2, 3, 4}, CW_(p)=CW_(min,p) is set.

2) If at least Z=80% of HARQ-ACK values corresponding to PDSCHtransmission(s) is determined to be NACK in a reference subframe k, theprocedure increases CW_(p) to a next highest permitted value for allpriority classes p∈{1, 2, 3, 4} and remains in step 2. If not, theprocedure proceeds to step 1.

The reference subframe k is a subframe in which most recent transmissionperformed by an eNB on a carrier expected to be available for at leastsome HARQ-ACK feedbacks starts.

The eNB needs to adjust the value of CW_(p) for all priority classesp∈{1, 2, 3, 4} only once on the basis of the given reference subframe k.

If CW_(p)=CW_(max,p), the next highest permitted value CW_(max,p) forCW_(p) adjustment.

When Z is determined,

-   -   If eNB transmission(s) available for HARQ-ACK feedback start at        the second slot of the subframe k, HARQ-ACK values corresponding        to PDSCH transmission(s) in a subframe k+1 can also be used by        being added to HARQ-ACK values corresponding to PDSCH        transmission(s) in the subframe k.    -   If HARQ-ACK values correspond to PDSCH transmission(s) on an LAA        SCell allocated according to an (E)PDCCH transmitted on the same        LAA SCell,        -   if the eNB has not detected HARQ-ACK feedback for PDSCH            transmission or the eNB detects “DTX”, “NACK/DTX” or “any”            state, it is computed as NACK.    -   If HARQ-ACK values correspond to PDSCH transmission(s) on an LAA        SCell allocated according to an (E)PDCCH transmitted on another        serving cell,        -   if HARQ-ACK feedback for PDSCH transmission is detected by            the eNB, “‘NACK/DTX” or “any” state is computed as NACK and            “DTX” state is ignored.        -   If HARQ-ACK feedback for PDSCH transmission is not detected            by the eNB,            -   if PUCCH format 1b using channel selection is expected                to be used by a UE, “NACK/DTX” state corresponding to                “no transmission” is computed as NACK and “DTX” state                corresponding to “no transmission” is ignored. If not,                HARQ-ACK for PDSCH transmission is ignored.    -   If PDSCH transmission has two codewords, a HARQ-ACK value of        each codeword is separately considered.    -   Bundled HARQ-ACK over M subframes is considered as M HARQ-ACK        responses.

If the eNB performs transmission that includes a PDCCH/EPDCCH having DCIformat 0A/0B/4A/4B and does not include a PDSCH associated with channelaccess priority class p on a channel starting at a time t₀, the eNBmaintains the contention window value CW_(p) and, adjusts CW_(p) fortransmissions using the following steps prior to step 1 of theabove-described procedure.

1) For all priority classes p∈{1, 2, 3, 4}, CW_(p)=CW_(min,p) is set.

2) When 10% or less of UL transport blocks scheduled by the eNB has beensuccessfully received using type-2 channel access procedure within aninterval from t₀ to t₀+T_(CO), the procedure increases CW_(p) to a nexthighest permitted value for all priority classes p∈{1, 2, 3, 4} andremains in step 2. If not, the procedure proceeds to step 1.

Here, T_(CO) is calculated as described in a channel access procedurefor uplink transmission(s) described below.

If CW_(p)=CW_(max,p) is consecutively used K times for generation ofN_(init), CW_(p) is reset to CW_(min,p) only for a priority class p atwhich CW_(p)=CW_(max,p) is consecutively used K times for generation ofN_(init). K is selected by the eNB from a set of values of {1, 2, . . ., 8} for each of priority classes p∈{1, 2, 3, 4}.

Hereinafter, an energy detection threshold adaptation procedure will bedescribed.

An eNB which is accessing a carrier on which transmission(s) of LAASCell(s) are performed needs to set the energy detection thresholdX_(Thresh) to be equal to or less than a maximum energy detectionthreshold X_(Thresh_max).

X_(Thresh_max) is determined as described later.

-   -   If absence of other technologies sharing carriers can be ensured        in the long term (for example, according to a level of        regulation),        X _(Thresh_max)=min{T _(max)+10 dB,X _(r)}.        -   Xr is a maximum energy detection threshold defined in dB            according to regulatory requirements when the regulatory            requirements are defined. If not, X_(r)=T_(max)+10 dB.    -   If not,        X _(Thresh_max)=max{−72+10*log 10(BWMHz/20 Mhz)dBm,min{T _(max)        ,T _(max) −T _(A)+(P _(H)+10*log 10(BWMHz/20 MHz)−P _(TX))}}.    -   Here,        -   T_(A)=10 dB for transmission(s) including a PDSCH.        -   T_(A)=5 dB for transmissions including discovery signal            transmission(s) without a PDSCH.        -   P_(H)=23 dBm.        -   PTX is the set maximum eNB output power in dBm with respect            to a carrier.            -   An eNB uses the maximum transmission power set with                respect to a single carrier irrespective of whether a                single carrier transmission or multi-carrier                transmission is used.                T _(max)(dBm)=10*log                10(3.16228*10⁻⁸(mW/MHz)*BWMHz(MHz)).        -   BWMHz is a single carrier bandwidth in MHz.

Hereinafter, a channel access procedure for transmission(s) on aplurality of carriers will be described.

An eNB can access a plurality of carriers on which transmission(s) ofLAA SCells are performed according to one of type-A and type-Bprocedures described later.

Hereinafter, a type-A multi-carrier access procedure will be described.

An eNB needs to perform channel access on each carrier c_(i)∈C accordingto the aforementioned channel access procedure for transmission(s)including a PDSCH/PDCCH/EPDCCH. Here, C is a set of carriers intended tobe transmitted by the eNB, i=0, 1, . . . , q−1, and q is the number ofcarriers intended to be transmitted by the eNB.

The counter N described in the aforementioned channel access procedurefor transmission(s) including a DSCH/PDCCH/EPDCCH is determined for eachcarrier c_(i)(c_i) and represented as N_(c_i). N_(c_i) is maintained intype A1 or type A2.

Hereinafter, type A1 will be described.

The counter N described in the aforementioned channel access procedurefor transmission(s) including a DSCH/PDCCH/EPDCCH is determined for eachcarrier c_(i) and represented as N_(c_i).

If absence of other technologies sharing carriers is not ensured in thelong term (for example, according to a level of regulation), when theeNB stops transmission on any one carrier c_(j)∈C, the eNB can resumeN_(c_i) reduction for each carrier c_(i)≠c_(j) after idle slots aresensed after waiting for a duration of 4T_(sl) or after N_(c_i) isreinitialized.

Hereinafter, type A2 will be described.

The counter N described in the aforementioned channel access procedurefor transmission(s) including a DSCH/PDCCH/EPDCCH is determined for acarrier c_(j)∈C and represented as N_(c_j). Here, c_(j) is a carrierhaving a largest CW_(p) value. For each carrier c_(i), N_(c_i)=N_(c_j).When the eNB stops transmission on any one carrier for which N_(c_i) hasbeen determined, the eNB needs to reinitialize N_(c_i) for all carriers.

Hereinafter, a type-B multi-carrier access procedure will be described.

A carrier c_(j)∈C is selected by an eNB as follows.

-   -   The eNB uniformly randomly selects c_(j) from C prior to        respective transmissions on a plurality of carriers c_(i)∈C, or    -   the eNB does not select c_(j) more than once per second.

Here, C is a set of carriers intended to be transmitted by the eNB, i is0, 1, . . . , q−1, and q is the number of carriers intended to betransmitted by the eNB.

For transmission on a carrier c_(j),

-   -   the eNB needs to perform channel access on a carrier c_(j)        according to the aforementioned channel access procedure        including a PDSCH/PDCCH/EPDCCH having a modification for type B1        or type B described below.

For transmission on a carrier corresponding to c_(i)∈C and c_(i)≠c_(j),

-   -   for each carrier c_(i), the eNB needs to sense the carrier c_(i)        for at least the sensing interval T_(mc)=25 μs immediately        before transmission on the carrier c_(j) and the eNB can perform        transmission on the carrier c_(i) immediately after sensing that        the carrier c_(i) is idle for at least the sensing interval        T_(mc). The carrier c_(i) is considered to be idle for T_(mc) if        it is sensed that a channel is idle for all time intervals in        which idle sensing is performed on the carrier c_(j) within the        given interval T_(mc).

The eNB should not continuously perform transmission on a carriercorresponding to c_(i)∈C, c_(i)≠c_(j) for a period that exceedsT_(mcot,p) given in Table 4. Here, the value of T_(mcot,p) is determinedusing a channel access parameter used for carriers c_(j).

Hereinafter, type B1 will be described.

A single CW_(p) value is maintained for a set C of carriers

When CW_(p) is determined for channel access on a carrier c_(j), step 2described in the contention window adjustment procedure is modified asfollows.

-   -   If at least Z=80% of HARQ-ACK values corresponding to PDSCH        transmission(s) in reference subframes k of all carriers c_(i)∈C        is determined to be NACK, the procedure increases CW_(p) to a        next highest permitted value for respective priority classes        p∈{1, 2, 3, 4}. If not, the procedure proceeds to step 1.

Hereinafter, type B2 will be described.

CW_(p) is independently maintained for each carrier c_(i)∈C using theaforementioned contention window adjustment procedure.

When N_(init) is determined for carriers c_(j), the value of CW_(p) of acarrier c_(j1)∈C is used. Here, c_(j1) is a carrier having a largestCW_(p) value among all carriers in the set C.

Hereinafter, an uplink channel access procedure will be described.

A UE and an eNB which schedules uplink transmission(s) for the UE needto perform the following procedures to access channel(s) on whichtransmission(s) of LAA SCell(s) are performed for the UE.

Hereinafter, a channel access procedure for uplink transmission(s) willbe described.

A UE can access a carrier on which uplink transmission(s) of LAASCell(s) are performed according to one of type-1 and type-2 uplinkchannel access procedures. The type 1 channel access procedure and thetype 2 channel access procedure will be described later.

If an uplink grant that schedules PUSCH transmission indicates thetype-1 channel access procedure, the UE needs to use the type-1 channelaccess procedure in order to perform transmissions including PUSCHtransmission unless otherwise described.

If the uplink grant that schedules PUSCH transmission indicates thetype-2 channel access procedure, the UE needs to use the type-2 channelaccess procedure in order to perform transmissions including PUSCHtransmission unless otherwise described.

The UE needs to use the type-1 channel access procedure when the UEperforms SRS transmissions including no PUSCH transmission. An uplinkchannel access priority class p=1 is used for SRS transmissionsincluding no PUSCH.

Table 6 shows a channel access priority class for uplink.

TABLE 6 Channel access priority Permitted class (p) m_(p) CW_(min,p)CW_(max,p) T_(ulmcot,p) CW_(p) value 1 2  3   7 2 ms {3, 7} 2 2  7  15 3ms {7, 15} 3 3 15 1023 6 ms or 10 ms {15, 31, 63, 127, 255, 511, 1023} 47 15 1023 6 ms or 10 ms {15, 31, 63, 127, 255, 511, 1023} Note 1:T_(ulmcot,p) = 10 ms if higher layer parameter‘absenceOfAnyOtherTechnology-r14’ indicates TRUE for p = 3, 4 andT_(ulmcot,p) = 6 ms if not. Note 2: When T_(ulmcot,p) = 6 ms, this canbe increased to 8 ms by inserting one or more gaps. A minimum gapduration must be 100 μs. A maximum duration before insertion of any gapmust be 6 ms.

When “UL configuration for LAA” field configures “UL offset” l and “ULduration” d for a subframe n,

if end of UE transmission occurs within or before a subframe n+l+d−1,the UE can use channel access type 2 for transmissions within a subframen+l+i irrespective of channel access type signaled by an uplink grantfor such subframes, and i=0, 1, . . . , d−1.

When the UE has scheduled transmissions including a PUSCH in a set ofsubframes n₀, n₁, . . . , n_(w−1) using PDCCH DCI format 0B/4B and hasnot accessed a channel for transmission in a subframe n_(k), the UEneeds to attempt transmission in a subframe n_(k+1) according to achannel access type indicated in DCI. Here, k∈{0, 1, . . . , w−2} and wis the number of scheduled subframes indicated in the DCI.

If the UE is scheduled to perform transmissions which do not have gapsincluding a PUSCH in the set of subframes n₀, n₁, . . . , n_(w−1) usingone or more PDCCH DCI formats 0A/0B/4A/4B and performs transmission in asubframe n_(k) after accessing a carrier according to one of the type-1and type-2 uplink channel access procedures, the UE can continuetransmission in subframes after n_(k). Here, k∈{0, 1, . . . , w−1}.

If the start of UE transmission in a subframe n+1 is immediately afterthe end of UE transmission in a subframe n, the UE does not expectindication of different channel access types for transmissions in suchsubframes.

When the UE is scheduled to perform transmission without a gap insubframes n₀, n₁, . . . , n_(w−1) using one or more PDCCH DCI formats0A/0B/4A/4B, has stopped transmission for or before a subframe n_(k1)for which k1∈{0, 1, . . . , w−2}, and senses that a channel iscontinuously idle after transmission has been stopped, the UE canperform transmission in the following subframe n_(k2) for which k2∈{1, .. . , w−1} using the type-2 channel access procedure. If the channelsensed by the UE is not continuously idle after the UE stopstransmission, the UE can perform transmission in the following subframen_(k2) for which k2∈{1, . . . , w−1} using a type-1 channel accessprocedure having an uplink channel access priority class indicated inDCI corresponding to the subframe n_(k2).

If the UE receives a UL grant, DCI indicates PUSCH transmission whichstarts in a subframe n using a type-1 channel access procedure and theUE has an ongoing type-1 channel access procedure before the subframe n,

-   -   If an uplink channel access priority class value p₁ used for the        continuous type-1 channel access procedure is equal to or        greater than an uplink channel access priority class value p₂        indicated by DCI, the UE can perform PUSCH transmission in        response to the UL grant by accessing a carrier using the        continuous type-1 channel access procedure.    -   If the uplink channel access priority class value p₁ used for        the continuous type-1 channel access procedure is less than the        uplink channel access priority class value p₂ indicated by the        DCI, the UE needs to end the continuous channel access        procedure.

If the UE is scheduled to perform transmission on the set C of carriersin the subframe n, UL grants which schedule PUSCH transmissions on theset C of carriers indicate the type-1 channel access procedure, the same“PUSCH starting position” is indicated by all carriers in the set C ofcarriers, and carrier frequencies of the set C of carriers are a subsetof predefined sets of carrier frequencies,

-   -   the UE can perform transmission on a carrier c_(i)∈C using the        type-2 channel access procedure in the following case.        -   If the type-2 channel access procedure is performed on the            carrier c_(i) immediately before UE transmission on a            carrier corresponding to c_(j)∈C, i≠j and        -   when the UE has accessed a carrier c_(j) using the type-1            channel access procedure,            -   here, the carrier c_(j) is uniformly randomly selected                by the UE from the set C of carriers before the type-1                channel access procedure is performed on any carrier in                the set C of carriers.

When an eNB has performed transmission on a carrier according to achannel access procedure for transmission(s) including aPDSCH/PDCCH/EPDCCH, the eNB can indicate the type-2 channel accessprocedure in DCI of a UL grant which schedules transmission(s) includinga PUSCH on a carrier in the subframe n. Alternatively, when the eNB hasperformed transmission on a carrier according to the channel accessprocedure for transmission(s) including a PDSCH/PDCCH/EPDCCH, the eNBcan indicate that the type-2 channel access procedure fortransmission(s) including a PUSCH on a carrier can be performed in thesubframe n using “UL configuration for LAA” field. Alternatively, whenthe subframe n is generated within a time interval that starts at to andends at t₀+T_(CO), the eNB can schedule transmissions including a PUSCHon a carrier in the subframe n, which follow transmission by the eNB ona carrier having a duration of T_(short_ul)=25 μs. Here,T_(CO)=T_(mcot,p)+T_(g),

-   -   t₀ is a time instance at which an eNB starts transmission,    -   the value of T_(mcot,p) is determined by an eNB as described in        the downlink channel access procedure,    -   T_(g) is a total time interval of gaps of all durations which        exceed 25 μs generated between downlink transmission of an eNB        and uplink transmission scheduled by the eNB and between        arbitrary two uplink transmissions which start at to and are        scheduled by the eNB.

If continuous scheduling is possible, the eNB needs to schedule uplinktransmissions between t₀ and t₀+T_(CO) in consecutive subframes.

For uplink transmission on a carrier which follows transmission by theeNB on a carrier having a duration of T_(short_ul)=25 μs, the UE can usethe type-2 channel access procedure.

If the eNB indicates the type-2 channel access procedure for the UE inDCI, the eNB indicates a channel access priority class used to acquireaccess to a channel in the DCI.

Hereinafter, a type-1 uplink channel access procedure will be described.

The UE can perform transmission using the type-1 channel accessprocedure after sensing that a channel is idle first for a slot durationof a defer duration T_(d) and after the counter N is 0 in step 4. Thecounter N is adjusted by sensing a channel with respect to additionalslot duration(s) according to the following steps.

1) N=N_(init) is set. Here, N_(init) is an arbitrary number uniformlydistributed between 0 and CW_(p). Then, the procedure proceeds to step4.

2) If N>0 and the eNB selects decrease of the counter, N=N−1 is set.

3) If a channel with respect to an additional slot duration is sensedand the additional slot duration is idle, the procedure proceeds to step4. If not, the procedure proceeds to step 5.

4) The procedure ends if N=0 and proceeds to step 2 if not.

5) The channel is sensed until a busy slot is detected within anadditional defer duration T_(d) or it is sensed that all slots of theadditional defer duration T_(d) are idle.

6) If it is sensed that the channel is idle for all slot durations ofthe additional defer duration T_(d), the procedure proceeds to step 4.If not, the procedure proceeds to step 5.

When the UE has not performed transmission including PUSCH transmissionon a carrier on which transmission(s) of LAA SCell(s) are performedafter step 4 of the above-described procedure, the UE can performtransmission including PUSCH transmission on the carrier if it is sensedthat a channel is idle in at least the slot duration T_(sl) when the UEis ready to perform transmission including PUSCH transmission and it issensed that the channel is idle for all slot durations of the deferduration T_(d) immediately before transmission including PUSCHtransmission. If it is not sensed that the channel is idle in the slotduration T_(sl) when the UE has initially sensed the channel after theUE is ready to perform transmission or it is not sensed that the channelis idle for arbitrary slot durations of the defer duration T_(d)immediately before intended transmission including PUSCH transmission,the UE senses that the channel is idle for slot durations of the deferduration T_(d) and then proceeds to step 1.

The defer duration T_(d) is configured as a duration of T_(f)=16 μsimmediately after consecutive slot durations m_(p). Here, each slotduration is T_(sl)=9 μs and T_(f) includes an idle slot duration T_(sl)at the start point of T_(f).

The slot duration T_(sl) is considered to be idle if the UE senses thechannel for the slot duration and power detected by the UE for at least4 μs in the slot duration is less than the energy detection thresholdX_(Thresh). If not, the slot duration Tsiis considered to be busy.

CW_(p)(CW_(min,p)≤CW_(p)≤CW_(max,p)) is a contention window. Adjustmentof CW_(p) will be described in the contention window adjustmentprocedure.

CW_(min,p) and CW_(max,p) are selected before the aforementioned step 1.

m_(p), CW_(min,p) and CW_(max,p) are based on a channel access priorityclass signaled to the UE as shown in Table 4.

X_(Thresh) adaptation will be described in an energy detection thresholdadaptation procedure which will be described later.

Hereinafter, a type-2UL channel access procedure will be described.

If an uplink UE uses a type-2 channel access procedure for transmissionincluding PUSCH transmission, the UE can perform transmission includingPUSCH transmission immediately after sensing that a channel is idle forat least a sensing interval of T_(short_ul)=25 μs. T_(short_ul) isconfigured as a duration of T_(f)=16 μs immediately followed by one shotduration of T_(sl)=9 μs, and T_(f) includes an idle slot duration T_(sl)at the start point of T_(f). If a channel is sensed as being idle forslot durations of T_(short_ul), the channel is considered to be idle forT_(short_ul).

Hereinafter, the contention window adjustment procedure will bedescribed.

If a UE performs transmission using the type-1 channel access procedureassociated with a channel access priority class p on a carrier, the UEneeds to maintain a contention window value CW_(p) and adjust CW_(p) forsuch transmissions before step 1 of the aforementioned type-1 uplinkchannel access procedure using the following procedures.

-   -   If an NDI value with respect to at least one HARQ procedure        associated with HARQ_ID_ref is toggled,        -   CW_(p)=CW_(min,p) is set for all priority classes p∈{1, 2,            3, 4}.    -   If not, CW_(p) is increased to a next highest permitted value        for all the priority classes p∈{1, 2, 3, 4}.

HARQ_ID_ref is a HARQ process ID of UL-SCH in a reference subframen_(ref). The reference subframe nrefis determined as follows.

-   -   When the UE has received an uplink grant in a subframe n_(g), a        subframe n_(w) is a most recent subframe prior to a subframe        n_(g)−3 in which the UE has transmitted UL-SCH using the type-1        channel access procedure.        -   If the UE performs transmission which starts in a subframe            n₀ without gaps and includes UL-SCH in subframes n₀, n₁, . .            . , n_(w), the reference subframe n_(ref) is the subframe            n₀,        -   If not, the reference subframe n_(ref) is the subframe            n_(w).

If the UE is scheduled to perform transmissions including PUSCHtransmission without gaps in a set of subframes n₀, n₁, . . . , n_(w−1)using the type-1 channel access procedure and any transmission includingPUSCH transmission cannot be performed in the set of subframes, the UEcan maintain the value of CW_(p) without changing the same for allpriority classes p∈{1, 2, 3, 4}.

If a reference subframe for finally scheduled transmission is alson_(ref), the UE can maintain the value of CW_(p) for all priorityclasses p∈{1, 2, 3, 4} using the type-1 channel access procedure as infinally scheduled transmission including PUSCH transmission.

If CW_(p)=CW_(max,p), a next highest permitted value for CW_(p)adjustment is CW_(max,p).

If CW_(p)=CW_(max,p) is consecutively used K times for generation ofN_(init), CW_(p) is reset to CW_(min,p) only for a priority class p atwhich CW_(p)=CW_(max,p) is consecutively used K times for generation ofN_(init). K is selected by the UE from a set of values of {1, 2, . . . ,8} for each of the priority classes p∈{1, 2, 3, 4}.

Hereinafter, energy detection threshold adaptation procedure.

A UE which has accessed a carrier on which transmission(s) of LAASCell(s) are performed needs to set the energy detection thresholdX_(Thresh) to below a maximum energy detection threshold X_(Thresh_max).

X_(Thresh_max) is determined as follows.

-   -   If the UE is configured by higher layer parameter        “maxEnergyDetectionThreshold-r14”,        -   X_(Thresh_max) is set to the same value as a value signaled            by the higher layer parameter.    -   If not,        -   the UE needs to determine X′_(Thresh_max) according to a            default maximum energy detection threshold computation            procedure which will be described later.        -   If the UE is configured by higher layer parameter            “energyDetectionThresholdOffset-r14”,            -   X_(Thresh_max) is set by applying X′_(Thresh_max)                according to an offset value signaled by the higher                layer parameter.        -   If not,            -   the UE needs to set X_(Thresh_max)=X′_(Thresh_max).

Hereinafter, the default maximum energy detection threshold computationprocedure will be described.

If higher layer parameter “absenceOfAnyOtherTechnology-r14” indicates“TRUE”:X′ _(Thresh_max)=min{T _(max)+10 dB,X _(r)}, here,

-   -   X_(r) is a maximum energy detection threshold defined in dBm        according to regulatory requirements when the regulatory        requirements are defined. If not X_(r)=T_(max)+10 dB.

If not,X′ _(Thresh_max)=max{−72+10*log 10(BWMHz/20 MHz)dBm,min{T _(max) ,T_(max) −T _(A)+(P _(H)+10*log 10(BWMHz/20 MHz)−P _(TX))}}

Here,

-   -   T_(A)=10 dB    -   P_(H)=23 dBm    -   P_(TX) is set to P_(CMAX_H,c).        T _(max)(dBm)=10*log 10(3.16228*10⁻⁸(mW/MHz)*BWMHz(MHz))    -   BWMHz is a single carrier bandwidth in MHz.

Hereinafter, the present disclosure will be described.

With demands for greater communication capacity from a growing number ofcommunication devices, the efficient utilization of a limited frequencyband is becoming an increasingly important requirement for futurewireless communication systems. Cellular communication systems, such asLTE/NR systems, are also considering using an unlicensed band, forexample a 2.4 GHz band generally used by an existing Wi-Fi system or 5GHz and 60 GHz bands newly emerging, for traffic offloading.

FIG. 18 illustrates an example of a wireless communication systemsupporting an unlicensed band.

Referring to FIG. 18 , a cell operating in a license band (hereinafter,also referred to as an L-band) may be defined as an L-cell, and acarrier of the L-cell may be referred to as a (DL/UL) LCC. Further, acell operating in an unlicensed band (hereinafter, also referred to as aU-band) may be defined as a U-cell, and a carrier of the U-cell may bereferred to as a (DL/UL) UCC. A carrier/carrier-frequency of a cell mayrefer to an operating frequency (e.g., center frequency) of the cell. Acell/carrier (e.g., component carrier (CC)) may be collectively referredto as a cell.

As illustrated in FIG. 18(a), when a UE and a base station transmit andreceive signals through an LCC and a UCC which are subjected to carrieraggregation, the LCC may be set as a primary CC (PCC) and the UCC may beset as a secondary CC (SCC). Alternatively, as illustrated in FIG.18(b), the UE and the base station may transmit and receive signalsthrough a single UCC or a plurality of UCCs subjected to carrieraggregation. That is, the UE and the base station may transmit andreceive signals only through a UCC(s) without any LCC.

Hereinafter, a signal transmission/reception operation in an unlicensedband described above in the present disclosure may be performed based onall the above-described deployment scenarios (unless specifiedotherwise).

In an unlicensed band, a method of performing wireless transmission andreception through contention between communication nodes may be assumed.Therefore, it is required that each communication node performs channelsensing before transmitting a signal to verify that a differentcommunication node is not performing signal transmission. Forconvenience, this operation is referred to as a listen-before-talk (LBT)or a channel access procedure (CAP).

In particular, an operation of verifying whether the differentcommunication node is performing signal transmission may be referred toas carrier sensing (CS), and a case where it is determined that thedifferent communication node is not performing signal transmission maybe referred to as a clear channel assessment (CCA) having been verified.

A base station (eNB) or a UE of an LTE/NR system also needs to performan LBT for signal transmission in an unlicensed band (U-band). When thebase station or the UE of the LTE/NR system transmits a signal, othercommunication nodes, such as a Wi-Fi node, also need to perform an LBTso as not to cause interference. For example, in the Wi-Fi standard(801.11ac), a CCA threshold is defined as −62 dBm for a non-Wi-Fi signaland as −82 dBm for a Wi-Fi signal. That is, a station (STA, UE) or anaccess point (AP) does not transmit a signal so as not to causeinterference when a signal other than a Wi-Fi signal is received with apower of −62 dBm or more.

For the UE to transmit uplink data in the unlicensed band, first, thebase station needs to succeed in an LBT for UL grant transmission in theunlicensed band, and the UE also needs to succeed in an LBT for UL datatransmission. That is, the UE can attempt UL data transmission only whenboth LBTs of the base station and the UE are successful.

Further, in the LTE system, a delay of at least 4 msec is requiredbetween an UL grant and UL data scheduled through the UL grant.Therefore, if a different transmission node coexisting in the unlicensedband achieves access first during the corresponding time, scheduled ULdata transmission may be delayed. For this reason, a method forincreasing efficiency of UL data transmission in the unlicensed band isunder discussion.

In LTE licensed-assisted access (LAA), a base station may report asubframe or slot allowed/available for an autonomous uplink (AUL) to aUE through a bitmap of X bits (e.g., X=40 bits), and thus the basestation may report autonomous UL transmission of transmitting UL datawithout a UL grant to the UE.

When receiving an indication of automatic transmission activation (autoTx activation), the UE can transmit uplink data without a UL grant inthe subframe or slot indicated by the bitmap. Just as the base stationtransmits a PDCCH, which is scheduling information necessary fordecoding, when transmitting a PDSCH to the UE, the UE may transmit AULUCI, which is information necessary for the base station to decode aPUSCH, when transmitting the PUSCH in an AUL.

The AUL UCI may include information necessary to receive an AUL PUSCH,such as an HARQ ID, a new data indicator (NDI), a redundancy version(RV), a starting AUL subframe (SF) position, and a last AUL SF position,and information for sharing a UE-initiated COT with the base station.

Specifically, sharing a UE-initiated COT with the base station refers toan operation that enables the UE to transfer some of occupied channelsto the base station through a random-backoff category-4 LBT (or type-1channel access procedure) and the base station to transmit a PDCCH(and/or PDSCH) when a channel is idle through a one-shot LBT of 25 usec(using a timing gap provided by the UE emptying the last symbol).

In NR, in order to support UL transmission with relatively highreliability and low latency, the base station also supports time-domain,frequency-domain, and code-domain resources as configured grant type 1(hereinafter, also referred to as type 1) and configured grant type 2(hereinafter, also referred to as type 2) configured for the UE throughi) a higher-layer signal (e.g., RRC signaling) or ii) a combination of ahigher-layer signal and an L1 (physical-layer) signal (e.g., DCI).

The UE may perform UL transmission using a resource configured as type 1or type 2 without receiving a UL grant from the base station. For type1, all of the period of a configured grant, an offset relative to systemframe number (SFN)=0, time/frequency resource allocation, the number ofrepetitions, a DMRS parameter, a modulation and coding scheme(MCS)/transport block size (TBS), a power control parameter and the likemay be configured only with a higher-layer signal, such as RRCsignaling, without an L1 signal. For type 2, the period of a configuredgrant, and a power control parameter are configured through ahigher-layer signal, such as RRC signaling, and remaining resourceinformation (e.g., an offset of initial transmission timing,time/frequency resource allocation, a DMRS parameter, an MCS/TBS, andthe like) is indicated through activation DCI, which is an L1 signal.

The AUL of LTE LAA and the configured grant method of NR aresignificantly different in an HARQ-ACK feedback transmission method fora PUSCH transmitted by a UE without a UL grant and whether there is UCItransmitted together with a PUSCH.

Regarding an HARQ-ACK feedback transmission method, explicit HARQ-ACKfeedback information is transmitted through AUL-downlink feedbackinformation (DFI) in LTE LAA, whereas an HARQ process is (implicitly)determined using a symbol index, a symbol period, and as many equationsas the number of HARQ processes in the configured grant method of NR.

Regarding UCI transmitted together with a PUSCH, in LTE LAA, informationincluding an HARQ ID, an NDI, and an RV is transmitted as AUL-UCIwhenever an AUL PUSCH is transmitted. In the configured grant method ofNR, a UE is recognized/identified using a time/frequency resource and aDMRS resource used by the UE for PUSCH transmission. In LTE LAA,however, a UE is recognized/identified using a DMRS resource and a UE IDexplicitly included in AUL-UCI transmitted together with a PUSCH.

The present disclosure proposes a method for allocating a time-domainresource considering a plurality of numerologies and a method fortransmitting confirmation information after receiving an activationindication from a base station in a case where the base station sets aconfigured grant for a UE in an unlicensed band. Further, the presentdisclosure proposes HARQ-ACK feedback timing of a base station for a ULburst (data) transmitted by a UE, the content of UCI, a UCI mappingmethod, and a method for supporting automatic retransmission without aUL grant.

Hereinafter, in this specification, for convenience, a configured grantin an unlicensed band is abbreviated to a CGU, and uplink controlinformation (UCI) and downlink feedback information (DFI) that functionsimilarly to AUL-UCI and AUL-DFI in a CGU are referred to as CGU-UCI andCGU-DFI, respectively.

<3.1 Method for Configuring CGU Resource Allocation, ActivationConfirmation Message Transmission, and Autonomous Retransmission>

[Proposed method #1] Method of differently configuring or interpreting abitmap according to numerology when a time-domain resource for CGU-PUSCHtransmission is allocated by the bitmap

Similarly to an LTE AUL, a slot capable of CGU-PUSCH transmission mayalso be configured in a bitmap in a CGU. For example, defining 0 and 1as a slot capable of CGU-PUSCH transmission and a slot incapable ofCGU-PUSCH transmission, respectively, a five-bit bitmap [0 1 1 0 1] maybe configured for a UE through a higher-layer signal, such as an RRCsignal. When one slot is 1 ms, the bitmap may be repeatedly appliedaccording to a period of 5 ms (i.e., subcarrier spacing (SCS)=15 kHz),and the UE may transmit a CGU-PUSCH in slots set to 1.

A method of initially configuring a bitmap based on the numerology of aninitial bandwidth part (BWP) or a default SCS and differentlyinterpreting the granularity of the bitmap depending on a change in SCSdue to a BWP change or a method of separately configuring a bit for eachSCS is possible.

For example, when the SCS is increased to 30 kHz, each bit of thefive-bit bitmap may be interpreted as being for two slots.Alternatively, a base station may configure a bitmap (e.g., a 10-bitbitmap) to be used for a 30-kHz SCS separately from the bitmap for the15-kHz SCS. As described above, the base station may allow a UE todifferently interpret an initially configured bitmap depending on SCS ormay configure a separate bitmap having a different size for each SCS(may change the number of bits depending on SCS). Alternatively, thebase station may indicate a method to be used (whether to differentlyinterpret a bitmap depending on SCS or to provide a separate bitmap foreach SCS) to the UE.

[Proposed method #2] Method in which a UE autonomously performsretransmission when a rescheduling UL grant or an HARQ-ACK feedbackresult through CGU-DFI is not indicated until slot X with respect to anHARQ process transmitted by the UE via a CGI-PUSCH

In LTE LAA, when a UE i) receives NACK feedback through AUL-DFI or ii)does not receive a rescheduling UL grant and AUL-DFI until subframe Xwith respect to an HARQ process transmitted via an AUL-PUSCH, the UEautonomously performs retransmission.

Likewise, in a CGU, when a rescheduling UL grant or an HARQ-ACK feedbackresult through CGU-DFI is not indicated until slot X with respect to anHARQ process transmitted via a CGU-PUSCH, a UE may autonomously performretransmission. Here, X may be a fixed value or a value that can be setby a base station. Further, X may be set for each UE per numerology or afixed value set for X may be differently interpreted and applieddepending on numerology. For example, when X=6 is set according toSCS=15 kHz, X may be interpreted and applied as 12 when SCS=30 kHz.Alternatively, X for SCS=30 kHz may be set for the UE separately fromthat for SCS=15 kHz.

[Proposal method #3] Method in which a UE transmits a confirmationmessage to a base station by performing an LBT with a low CCA thresholdor without CCA within the COT of the base station in order to quicklyrespond to reception of CGU activation DCI.

In an LTE AUL, resource allocation and activation may be performed usinga combination of an RRC signal, which is a higher-layer signal, andactivation DCI, which is an L1 signal. The UE transmits a confirmationmessage to the base station in response to reception of the activationDCI. Here, there is a possibility that an LBT for this transmission maybe delayed or fails due to occupancy of a channel by a different node orthe like.

Similarly to the AUL, a CGU may also be configured as a combination ofan RRC signal and activation DCI. Here, a confirmation message may beconfigured to be immediately transmitted without an LBT when transmittedby increasing a CCA threshold or by sharing the COT of the base stationwithin the CO in order to increase the LBT success rate of aconfirmation message for the activation DCI. Alternatively, when thereis a PUCCH for which a COT is shared before CGU-PUSCH transmission, theconfirmation message may be transmitted via the PUCCH by adding acorresponding confirmation bit to a UCI payload. As described above,when the CCA threshold for transmitting the confirmation message is sethigher than that for other transmissions or transmission is performedwithout an LBT in the COT, the confirmation message may be transmittedwith a short delay time and a high transmission probability.

[Proposed method #9] Method for allocating a plurality of slots or timeresources per slot for CGU-PUSCH transmission using at least one of thefollowing methods when a base station indicates data scheduling in aplurality of CGU slots (or CGU TTIs) to a UE using a time resourceallocation method according to an NR-U configured grant method, which isan application of a time resource allocation method according to the NRconfigured grant method

(1) Option 1

A. The base station indicates a single combination (e.g., {S0, L0}) of astarting symbol index and a length or duration, and the UE interpretsthe information as follows.

i. It may be interpreted that (consecutive) time resources starting fromS0 and having a length of L0 are allocated per CGU slot.

ii. CGU-PUSCH transmission per slot in the time resources may beassumed.

(2) Option 2

A. The base station may indicate a single combination (e.g., {S0, L0})of a starting symbol index and a length or duration, and the UE mayinterpret the information as follows.

i. It may be interpreted that (consecutive) time resources from S0 in afirst CGU slot to E0 in a last CGU slot are allocated (if L0 is apositive number).

ii. It may be interpreted that (consecutive) time resources from E0 inthe first CGU slot to S0 in the last CGU slot are allocated (if L0 is anegative number).

iii. E0 means the index of an ending symbol, and E0=S0+L0.

iv. CGU-PUSCH transmission per slot in the time resources may beassumed.

(3) Option 3

A. The base station may indicate a single combination of a startingsymbol index and a length (e.g., {S0, L0}) and mirroring (e.g., on/off)information, and the UE may interpret this information as follows.

i. It may be interpreted that (consecutive) time resources from S0 in afirst CGU slot to E0 in a last CGU slot are allocated (if mirroring isoff).

ii. It may be interpreted that (consecutive) time resources from E0 inthe first CGU slot to S0 in the last CGU slot are allocated (ifmirroring is on).

iii. E0 means the index of an ending symbol, and E0=S0+L0.

iv. CGU-PUSCH transmission per slot in the time resources may beassumed.

(4) Option 4

A. The base station may indicate N combinations of a starting symbolindex and a length (e.g., {S₀, L₀}, {S₁, L₁}, . . . , {S_(N−1),L_(N−1)}) for N CGU slots, and the UE may interpret this information asfollows.

i. It may be interpreted that (consecutive) time resources starting fromS_(n) and having a length of L_(n) are allocated per nth CGU slot (n=0,1, . . . , N−1).

ii. CGU-PUSCH transmission per CGU slot in the time resources may beassumed.

(5) Option 5

A. The base station indicates a single combination (e.g., {S0, L0}) of astarting symbol index and a length or duration, and the UE interpretsthe information as follows.

i. It may be interpreted that time resources starting from S0 in thefirst CGU slot and having a length of a multiple of L0 are allocated.

ii. CGU-PUSCH transmission per L0 in the time resources may be assumed.

(6) Option 6

A. The base station indicates a single combination (e.g., {S0, L0}) of astarting symbol index and a length or duration, and the UE interpretsthe information as follows.

i. It may be interpreted that (consecutive) time resources from S0 inthe first CGU slot to E0 in the last CGU slot are allocated.

ii E0 means the index of an ending symbol, and E0=S0+L0 mod S. S meansthe number of symbols in a slot, and S0+L0 may be allocated to be S orgreater.

iii. CGU-PUSCH transmission per CGU slot in the time resources may beassumed.

Data scheduling in a plurality of CGU slots (or CGU TTIs) proposed abovemay be applied to a corresponding slot after allocating transmissionresources per slot.

The base station may support one or more option(s) among the foregoingoption(s) and may indicate information on an actually used option to theUE through a higher-layer signal and/or DCI.

When the base station indicates a single or a plurality of combinationsof a starting symbol index and a length to the UE, the base station mayconfigure candidate groups of the combination(s) through a higher-layersignal, such as RRC signaling, and may then indicate one of thecandidate groups through DCI.

In the AUL of the LTE LAA system, a time-domain resource allocationmethod that configures a subframe capable of transmitting an AUL-PUSCHthrough an RRC bitmap of 40 bits may be used. In an NR-U system, timeresources for a CGU-PUSCH may be allocated in a bitmap format as in theAUL, but time resources for a CGU-PUSCH may also be allocated byapplying a time-domain resource allocation method in an NR configuredgrant.

NR configured grants may be largely divided into type 1 and type 2. Intype 1, time-frequency resources are allocated only through RRCconfiguration. In type 2, time-frequency resources are allocated througha combination of RRC configuration and activation DCI. However, the twotypes basically have the same time resource allocation method, in whicha time resource may be allocated by indicating/configuring a slot fortransmitting a grant configured with an offset relative to SFN=0, astarting symbol in the slot, and a transmission length through asymbol-based period value T and a repetition K per subcarrier spacing(SCS) and parameters ‘timeDomainAllocation’ and ‘timeDomainOffset’.

For example, when the offset is 0 and the period is T=56 based on a15-kHz subcarrier spacing, K=2, S=3, and L=6 which is 4*14, configuredgrant resource slots are slot 1, slot 2, slot 5, slot 6, slot 9, slot10, and the like, and six symbol resources from a third symbol in thecorresponding slots may be used for transmission.

An SLIV value indicated/configured by ‘timeDomainAllocation’ is definedas a combination of a predefined starting symbol and a transmissionlength/duration. If the time resource allocation method of the NRconfigured grant is applied to the CGU-PUSCH, it is necessary todifferently interpret S and L indicated by the SLIV in view ofcharacteristics of the NR-U system operating in an unlicensed band.

For example, when consecutive slots are allocated for the CGU-PUSCH, theNR PUSCH may be transmitted using only L symbols from symbol S in a slotinstead of all symbols in the slot. Therefore, when the transmission iscompleted before the last symbol of the slot, the transmission may becontinued only when a category-4 LBT is performed again and succeeds inthe starting symbol of the continuing next slot.

After allocating consecutive transmission slot resources through therepetition K or allocating transmission slot resources through aseparate per-slot allocation method, time resources for the CGU-PUSCH ina single slot or consecutive N slots may be allocated through the aboveoptions. That is, a combination of the index of a starting symbol in aCGU-PUSCH transmission slot and a (consecutive) data transmission length(based on the starting symbol) may be indicated by the SLIV value (thismethod may be referred to as a SLIV method hereinafter).

When indicating multi-TTI scheduling in an NR unlicensed band (U-band)according to an embodiment of the present disclosure, the resourceallocation method for the single slot may also be extensively applied toa method for allocating a time resource in a plurality of slots.

In one example, the base station indicates a single combination of astarting symbol index and a length (e.g., {S0, L0}), and the UE mayextensively interpret this information as allocating (consecutive) timeresources from S0 in a first TTI to E0 in a last TTI (option 1). Here,E0 is S0+L, which can refer to a last symbol index.

An aspect to be further considered is that a conventional relationshipof the last symbol index>the starting symbol index is always establishedsince the starting symbol index and the last symbol index indicated bythe SLIV are values for data transmission in the same slot (or the sameTTI), while a relationship of the last symbol index the starting symbolindex may also be established since the starting symbol index is appliedonly to the first TTI and the last symbol index is applied only to thelast TTI in the extended resource allocation method for multi-TTIscheduling.

To express this relationship in the SLIV method, it may be considered toindicate a length having a negative value (option 2) or to performmirroring such that the starting symbol index and the last symbol indexare respectively applied to the last TTI and the first TTI (option 3).

FIG. 19 illustrates a method for allocating time resources in aplurality of TTIs based on the SLIV method according to mirroringon/off.

Referring to FIG. 19 , a UE may interpret that (consecutive) timeresources from a starting symbol index in a first TTI to a last symbolindex in a last TTI are allocated (if mirroring is indicated as ‘off’).The UE may interpret that (consecutive) time resources from a lastsymbol index in the first TTI to a starting symbol index in the last TTIare allocated (if mirroring is indicated as ‘on’). That is, which of thefirst TTI and the last TTI the starting symbol index and the last symbolindex are applied to may vary depending on mirroring settings.

A general method in which a base station indicates N combinations of astarting symbol index and a length (e.g., {S₀, L₀}, {S₁, L₁}, . . . ,{S_(N−1), L_(N−1)}) for N TTIs may also be considered (option 4). Thebase station may configure candidate groups of the combination(s)through a higher-layer signal, such as RRC signaling, and may thenindicate one of the candidate groups through DCI.

[Proposed method #10] CGU time resource allocation method ascombination/mixing of a bitmap-based per-slot time resource allocationmethod configured via RRC and proposed method #9.

(1) All symbols in a slot configured as a CGU slot in a bitmap and allsymbols in a single slot or a plurality of slots allocated by proposedmethod #9 may be allocated as CGU transmission time resources.

(2) Only symbols in the intersection of a slot configured as a CGU slotin a bitmap and a single slot or a plurality of slots allocated byproposed method #9 may be allocated as CGU transmission time resources.

Here, the bitmap-based per-slot time resource allocation may beconfigured per numerology as in proposed method #1, or one bit (eachbit) of the bitmap may be interpreted differently according to thenumerology.

Since time resources may be allocated per slot through a bitmapconfigured via RRC, slots capable of transmitting a CGU-PUSCH may bedetermined. In addition, it is possible to allocate a single slot or aplurality of slots and symbol-unit time resources in each slot throughthe options proposed in proposed method #9. Therefore, by combining ormixing the two methods, as in method (1), all symbols in slots allocatedby the two resource allocation methods or some symbols in the slots maybe used as CGU-PUSCH transmission resources. Alternatively, as in method(2), when time resources are allocated by the two resource allocationmethods, only a slot indicated/configured as a transmission resource byboth of the two resource allocation methods or some symbols in the slotmay be used as CGU-PUSCH transmission resources.

[Proposed method #11] Method in which a UE indicates that a feedbackresult is not received to a base station through a CGU-PUSCH andrequests feedback (when a rescheduling UL grant or an HARQ-ACK feedbackresult through CGU-DFI is not indicated for a certain period) withrespect to an HARQ process transmitted through the CGU-PUSCH

In this method, when a UL grant indicating retransmission or feedbackthrough CGU-DFI is not received for a certain period after transmittinga CGU-PUSCH with respect to HARQ processes configured via a CGU usingconfigured time-frequency resources, a UE indicates that no feedback isreceived to the base station when transmitting a subsequent CGU-PUSCH,thereby inducing feedback.

The certain period may be a predefined time or a value that may beset/indicated by the base station, and information indicating that nofeedback has been received may be transmitted to the base station viaCGU-UCI whenever a CGU-PUSCH is subsequently transmitted.

Specifically, as in the case of the AUL of the LTE LAA system where a UEautonomously performs retransmission via an AUL-PUSCH when the UE i)receives NACK feedback through AUL-DFI or ii) does not receive arescheduling UL grant and AUL-DFI until subframe X with respect to anHARQ process transmitted via an AUL-PUSCH, the UE may indicate that nofeedback has been received through a CGU-PUSCH transmitted after slot Y(or Y ms) and may request feedback when failing to receive feedback,CGU-DFI or a retransmission UL grant, from the base station for slot Y(or Y ms) after transmitting a CGU-PUSCH.

[Proposed method #12] Method in which a base station configures andindicate a plurality of slots or time resources per slot for CGU-PUSCHtransmission through a higher-layer signal (e.g., RRC signaling), aphysical-layer signal (e.g., DCI), or a combination thereof whenindicating data scheduling in a plurality of CGU slots to a UE by a timeresource allocation method of an NR-U configured grant (e.g., configuresand indicates an X-bit bitmap indicating a slot capable of CGUtransmission and a CGU-PUSCH transmission unit (2-symbol, 7-symbol, or14-symbol) in the slot)

The X-bit bitmap may be configured for each numerology (e.g., subcarrierspacing) as in proposed method #1, or each bit of the bitmap may beinterpreted differently according to the numerology.

Similarly to the time resource allocation method of the AUL in LTE, thebase station may configure CGU slots capable of CGU-PUSCH transmissionusing the X-bit bitmap through a higher-layer signal, such as RRCsignaling. The configured CGU slots corresponding to the bitmap may beperiodically repeated.

The bitmap may be differently interpreted depending on the subcarrierspacing (SCS) of a CGU-PUSCH, or the bitmap may be configured for eachSCS (see proposed method #1). Also, a transmission unit (e.g., 2-symbol,7-symbol, or 14-symbol) for the CGU-PUSCH to be transmitted in the CGUslots may be indicated and configured by i) a physical-layer signal,such as DCI, ii) an RRC signal, or iii) a combination thereof.

For example, one of a 2-symbol, a 7-symbol, or a 14-symbol may beindicated through a specific two-bit field in CGU activation DCI. Here,2, 7, and 14 may correspond to divisors of the number of symbolsincluded in a slot. If the number of symbols in the slot is changed, theCGU-PUSCH transmission unit may be defined as a divisor of the number ofsymbols in the slot.

For example, when the CGU-PUSCH transmission unit is configured orindicated as a 2-symbol, seven PUSCHs in 2-symbols may be transmitted ineach slot configured as a CGU slot in the bitmap. When the transmissionunit is configured as a 7-symbol, two PUSCHs in 7-symbols may betransmitted in each CGU slot, and when the transmission unit isconfigured as a 14-symbol, one PUSCH may be transmitted in each CGUslot. When the transmission unit is a 14-symbol, if the UE performs anLBT on the slot boundary of a CGU slot but fails, PUSCH transmission isdropped in the CGU slot, and the UE may wait until the next configuredCGU slot and may attempt to retransmit the PUSCH.

However, in the case of a 2-symbol or 7-symbol unit, dropping may beperformed based on each symbol in a CGU slot. Therefore, in the case ofthe 2-symbol, there may be seven opportunities to attempt PUSCHtransmission in the slot. Accordingly, transmission units in each slotmay be considered as a plurality of (PUSCH) starting positions at whichthe UE can perform transmission when succeeding in an LBT. This timeresource allocation method not only enables a CGU slot to be flexiblyconfigured but also provides a UE with a plurality of opportunities toattempt an LBT or to attempt transmission within a slot.

[Proposed method #13] Method for allocating a plurality of CGU slots anda symbol-unit resource in each slot by combining/mixing a bitmap-basedper-slot time resource allocation method configured via RRC and a timeresource allocation method using an SLIV and periodicity of an NRconfigured grant.

(1) CGU slots may be allocated by transmitting an X-bit bitmapindicating a slot capable of CGU transmission through a higher-layersignal (e.g., RRC signaling).

(2) A CGU-PUSCH transmission symbol may be allocated within a slotallocated as a CGU slot using (i) a configured or indicated SLIV and(ii) periodicity.

(3) When consecutive CGU slots are allocated through the bitmap,CGU-PUSCH transmission symbols may be allocated without a gap using allsymbols from starting symbol S, indicated by the SLIV, as a startingsymbol in a foremost slot among the consecutive slots to S+L in a lastslot. For example, starting symbol S may be determined based on a symbolof the foremost slot, and S+L may be determined based on a symbol in thelast slot.

The X-bit bitmap may be configured for each numerology as in proposedmethod #1, or each bit of the bitmap may be interpreted differentlyaccording to the numerology. For example, it is assumed that a slotcorresponding to a bit indicated by 1 in the bitmap is referred to aslot capable of CGU transmission, the periodicity is a 7-symbol,starting symbol S indicated by the SLIV is symbol #1, and duration isindicated by L=5.

FIG. 20 illustrates a case where a nonconsecutive CGU slot is configuredby a bitmap.

Referring to FIG. 20 , CGU symbols starting frame symbol #1 and having alength of 5 indicated by an SLIV in a slot 131 configured as a CGU slotand symbol #8 to symbol #12 in the same slot due to a periodicity of 7are allocated as CGU PUSCH transmission symbols. When attempting an LBTin symbol #1 of the CGU slot 131 and succeeding in the LBT, a UE maytransmit a CGU-PUSCH using 12 symbols from symbol #1 to symbol #12(CGU-PUSCH #1).

In this case, based on a half-slot, symbol #1 to symbol #6 may beconfigured as one transport block (TB), and symbols #7 to symbol #12 maybe configured as a different TB. When failing in an LBT in symbol #1,the UE may attempt an LBT again in symbol #8, which is the next startingposition. When the LBT is successful in symbol #8, the UE may transmit aCGU-PUSCH using five symbols from symbol #8 to symbol #12 (CGU-PUSCH#2).

FIG. 21 illustrates a case where two consecutive CGU slots are allocatedby a bitmap.

Referring to FIG. 21 , two consecutive CGU slots may be allocated by abitmap. In this case, when an LBT is successful in symbol #1 143 of afirst CGU slot 141, a UE may transmit a CGU-PUSCH using all symbols fromsymbol #1 143 of the first slot to symbol #5 144, which corresponds toS+L, of a second CGU slot 142 (CGU-PUSCH #1).

When failing in the LBT in symbol #1 143 of the first CGU slot 141, theUE may reattempt an LBT in symbol #8 145, which is the next startingposition. When the LBT is successful in symbol #8 145, the UE maytransmit a CGU-PUSCH using all symbols from symbol #8 145 of the firstCGU slot 141 to symbol #5 144 of the second CGU slot 142 (CGU PUSCH #2).When failing in the LBT at both starting positions of the first CGU slot141, the UE may reattempt an LBT in symbol #1 146 of the second CGU slot142. When the LBT is successful in symbol #1 146 of the second CGU slot142, the UE may transmit a CGU-PUSCH using symbols from symbol #1 146 tosymbol #5 144 of the second CGU slot 142 (CGU PUSCH #3).

FIG. 22 illustrates another case where two consecutive CGU slots areallocated by a bitmap.

Referring to FIG. 22 , a CGU-PUSCH may also be transmitted in a lastslot 152 of consecutive CGU slots 151 and 152 using all CGU resourcesymbols allocated according to an SLIV and periodicity (CGU-PUSCH #1).

When the consecutive CGU slots are allocated and a CGU-PUSCH istransmitted without a gap using CGU resource symbols, the UE maytransmit the CGU-PUSCH by configuring an independent TB with theboundary of a half-slot in order to avoid ambiguity with a base station.

<3.2 Method for Setting Timeline Between CGU-PUSCH and CGU-DFI>

[Proposed method #4] Method in which a base station explicitly sets atime relationship between a CGU-PUSCH transmitted without a grant and anHARQ-ACK included in CGU-DFI based on UE capability information (N1 andN2) values reported by a UE.

The UE may initially report capability values N1 and N2 related toprocessing time thereof to the base station. Here, N1 may be time insymbols taken from reception of a PDSCH to transmission of a PUCCH, andN2 may be time in symbols taken from reception of a PDCCH totransmission of a PUSCH. The base station may indicate, to the UE, timeK1 in slots to transmit the PUCCH after receiving the PDSCH and time K2in slots to transmit the PUSCH after receiving the PDCCH inconsideration of the processing time capability of the UE and a timingadvance (TA).

In LTE LAA, the UE may not expect AUL-DFI including an HARQ-ACK feedbackresult on an AUL-PUSCH transmitted in subframe n before subframe n+4.The base station may transmit HARQ-ACK feedback regarding a CGU-PUSCH,transmitted by the UE through a resource configured without a grant, tothe UE through CGU-DFI similarly to the AUL-DFI. Here, the base stationmay set for the UE a relationship between HARQ-ACKs included in theCGU-DFI and when PUSCHs are transmitted. A timeline between the CGU-DFIand the CGU-PUSCH may be set by the base station for the UE using aarbitrary value, or may be set by the base station based on capabilityinformation reported by the UE as described above (e.g., min(K1, K2),min(K1), or min(K2), where min (X, Y) means the smallest value among Xand Y, and min(X) means the smallest of values X). Further, the UE mayoperate assuming a default value (e.g., four slots) when timelinesettings for DFI and a PUSCH are not received from the base station.

<3.3 Content of CGU-UCI and Mapping Method>

[Proposed method #5] Method of including information, such as UL powerfor UE transmission or a CCA threshold, in the content of CGU-UCI andusing the information when a UE-initiated COT is shared.

For example, in a situation where UE A transmits a CGU-PUSCH with uplinktransmission power P1 and shares a COT obtained through an LBT with abase station, the base station may attempt to transmit a PDSCH to UE Bwithin the shared COT of the UE. In this case, when CGU-UCI includespower-related information, such as the uplink transmission power of UE Aor a CCA threshold value, to enable the base station to know that UE Ais a cell-edge UE and thus has great uplink transmission power P1, thebase station may transmit a PDSCH to a different distant UE within theshared COT by adjusting the CCA threshold value.

In another example, when a UE relatively close to the base stationtransmits a CGU-PUSCH with small power, the downlink transmission powerof the base station to perform transmission in the shared COT may needto be set to be less than or equal to the transmission power of the UE.Here, when the uplink transmission power of the UE is a specific value Xor less, the base station may not perform downlink transmission eventhough receiving a COT sharing indication.

When a UE transmits a CGU-PUSCH, if a threshold used for an LBT isrelated to a UL power level and UL power for transmission by the UE issmall, the power will affect only nodes which are in a relatively narrowrange or which are relatively close to the UE, thus setting a CCAthreshold to be relatively high. Specifically, the UE may divide thepower level thereof into nonconsecutive Y steps and may report themaximum value among power levels smaller than UL power for transmissionby the UE via CGU-UCI. For example, if it is possible to report the ULpower of the UE through a two-bit field included in the CGU-UCI, the UEmay compare the UL power thereof with nonconsecutive four power levelsconfigured/indicated by the base station, may select the maximum valueamong power levels smaller than the power thereof, and may signal themaximum value to the base station.

[Proposed method #6] Method of using information related to NR UCI indecoding the NR UCI and a UL-SCH when the NR UCI (e.g., HARQ-ACK) ispiggybacked on a CGU-PUSCH by adding the information to the content ofCGU-UCI

In NR, when an HARQ-ACK is piggybacked on a PUSCH, the HARQ-ACK may bepunctured or rate-matched according to the payload size. Particularly,in the case of rate matching of the HARQ-ACK, when misrecognition occurswith a base station as to whether or this operation is applied, aproblem may occur in decoding the entire PUSCH. Accordingly, a UL grantindicates the help information (e.g., an HARQ-ACK payload size). Here,when the UL grant is transmitted in the form of fallback DCI, no helpinformation is indicated, and thus the UE may autonomously determinewhether to piggyback the HARQ-ACK piggyback (e.g., depending on whetherat least one PDSCH is received).

However, in the CGU, since there is a high possibility that a DL grantis missed due to LBT failure and interference from other nodes andtransmission is performed without a UL grant, it is impossible toindicate help information illustrated above. In this situation, it maynot be desirable for the UE to autonomously determine whether to performrate matching of an HARQ-ACK as in NR. Therefore, it may be consideredto signal CGU-UCI by adding information related to NR UCI piggybacked ona CGU-PUSCH to the content of the CGU-UCI.

For example, it may be stable that the UE transmits CGU-UCI by includingthe size of an HARQ-ACK payload configured by the UE and/or CSI part Iand/or CSI part II and/or information on an HARQ-ACK target DL slottherein, and the base station decodes the CGU-UCI first and decodesremaining NR UCI and UL-SCH based on the information.

FIG. 23 shows a method for transmitting uplink control information (UCI)by a UE in an unlicensed band according to an embodiment of the presentdisclosure.

Referring to FIG. 23 , the UE generates data and first UCI includinginformation needed to decode the data (S1210).

The UE transmits the data and the first UCI to a base station through aphysical uplink shared channel (PUSCH) in the unlicensed band (S1220).

Here, the PUSCH may be a CGI-PUSCH described above. The UE may alsotransmit CGU-UCI, which is information needed for the base station todecode the PUSCH, when transmitting the PUSCH (CGU-PUSCH) by a CGUmethod. This GCU-UCI may be referred to as the first UCI. The first UCImay include information on at least one of a hybrid automatic repeatrequest (HARQ) identity (ID) for the data, a new data indicator (NDI)for the data, a redundancy version (RV) for the data, and a startposition and an end position of a subframe for transmitting the data.The first UCI may further include information needed to receive thePUSCH and information for sharing a UE-initiated COT with the basestation.

As described above, NR UCI described above may be transmitted aspiggybacking on the CGU-PUSCH. The NR UCI is referred as second UCI forconvenience. When the second UCI is transmitted along with the data andthe first UCI to the base station through the PUSCH, the first UCI mayfurther include information needed to decode the second UCI. Forexample, the first UCI may indicate at least one of a payload size ofcontrol information (e.g., an HARQ-ACK, CSI part I, and CSI part II)included in the second UCI and information indicating a downlink slotfor the control information. The second UCI may include at least one ofACK/NACK information of different data received from the base station,CSI part I, and CSI part II.

FIG. 24 shows a specific example of applying proposed method #6.

A base station may perform an LBT process (S141) and may then provideCGU activation information and/or CGU configuration information to a UE(S142). The CGU activation information and/or the CGU configurationinformation may indicate, for example, a subframe or slot fortransmitting a CGU and may include an X-bit bitmap. A CGU subframe orCGU slot may be indicated through the bitmap.

When the UE receives an indication of activating CGU transmission, theUE may transmit uplink data without an uplink grant in the CGU subframeor CGU slot indicated by the bitmap. The UE may generate first UCI andsecond UCI (S143), may perform an LBT process (S144), and may transmitthe data, the first UCI, and the second UCI to the base station througha CGU-PUSCH (S145).

The base station may decode the data and the second UCI based on thefirst UCI (S146), may perform an LBT process (S147), and may transmitCGU-DFI to the UE (S148). The CGU-DFI may include an ACK/NACK of thedata.

Hereinafter, proposed method #7 illustrates a method for mapping firstUCI and second UCI to a resource when the first UCI and the second UCIare transmitted through a PUSCH. Proposed method #7 may be applied whenthe first UCI and the second UCI are transmitted along with data(expressed as being transmitted by piggybacking) but may also be appliedwhen only the first UCI and the second UCI are transmitted.

[Proposed method #7] CGU-UCI mapping method according to a DMRS positionin a slot or considering LBT failure.

Since a CGU is transmitted in an unlicensed band, a UE needs to performan LBT first in order to transmit a CGU-PUSCH. When there istransmission by a different RAN device in a channel for transmission anda measured energy value is greater than a CCA threshold, the channel isconsidered to be occupied. In this case, the transmission fails at aposition at which the transmission is originally intended to start andthe transmission time is deferred, and thus a preceding symbol of a slotmay be punctured or an LBT failure of failing to transmit the entireslot may occur.

When receiving a CGU-PUSCH, a base station may decode CGU-UCI and maydecode the remaining part based on the information. Therefore, if theCGU-UCI of relatively high importance is damaged, decoding may not bestably performed.

Accordingly, the CGU-UCI, which includes important information fordecoding the CGU-PUSCH, may be sequentially mapped in a frequency-firstmanner from the last symbol in a slot that is relatively less likely tobe damaged even though an LBT fails or a transmission start time isdeferred.

FIG. 25 illustrates an example of CGU-UCI mapping.

Referring to FIG. 25 , CGU-UCI may be sequentially mapped to subcarriersof a last symbol 161 in a slot and may then be sequentially mapped tosubcarriers of a previous symbol 162.

When NR UCI is piggybacked on a CGU-PUSCH, the CGU-UCI may be mappedfirst by the following method, and the NR UCI (e.g., an HARQ-ACK) maythen be mapped. According to this mapping method, a base station candecode the CGU-UCI first to identify a UE, or can know information, suchas the payload size of an HARQ-ACK of the NR UCI when information aboutthe NR UCI is included in the CGU-UCI, thus being useful to decode theremaining part of the CGU-PUSCH.

The CGU-UCI may be mapped first to a specific position of a PUSCHregion, and the NR UCI may be mapped to the remaining resourcesaccording to an existing NR UCI mapping method assuming that theposition mapped to the CGU-UCI is unavailable (like a DM-RS symbol orPT-RS). That is, when the CGU-UCI is referred to as first UCI and the NRUCI is referred to as second UCI, the first UCI may be mapped first toresources among the resources for transmitting the PUSCH, and the secondUCI may be mapped to the remaining resources (using the existingmethod).

The base station may configure the UE to add a plurality of DMRS to aslot for transmitting the CGU-PUSCH, and the UE may map the CGU-UCI inthe frequency-first manner from the right symbol of a symbol where alast DMRS is positioned. In this mapping method, mapping is started fromthe right symbol of the symbol where the last DMRS is positionedconsidering that a preceding symbol and a DMRS are likely to be damaged(e.g., punctured) due to an LBT failure, thus reducing the probabilityof UCI loss.

That is, when the CGU-UCI is referred to as the first UCI and the NR UCIis referred to as the second UCI, a resource mapped to the first UCIamong the resources for transmitting the PUSCH may follow a resourcemapped to the second UCI. For example, the first UCI may be mapped to asymbol immediately after a demodulation reference signal (DMRS) symbolfor transmitting a DMRS among a plurality of symbols forming theresources for transmitting the PUSCH, and the second UCI may be mappedto a symbol before the DMRS symbol.

FIG. 26 illustrates another example of CGU-UCI mapping.

Referring to FIG. 26 , two DMRSs 171 and 172 may be configured in aCGU-PUSCH slot. Here, CGU-UCI may be mapped in the frequency-firstmanner from the right symbol 173 of a second DMRS symbol 172. If threeDMRSs are configured in the slot, the CGU-UCI may be mapped to from theright symbol of a third DMRS symbol.

FIG. 27 illustrates still another example of CGU-UCI mapping.

Referring to FIG. 27 , when NR UCI is piggybacked on a CGU-PUSCH,CGU-UCI may be mapped to a position before the mapping position of NRUCI (e.g., an HARQ-ACK). That is, the CGU-UCI may be mapped to the left(front) symbol 182 of a DMRS symbol 181, and the NR UCI (e.g., theHARQ-ACK) may be mapped to the right (back) symbol 183.

That is, when the CGU-UCI is referred to as first UCI and the NR UCI isreferred to as second UCI, a resource mapped to the first UCI amongresources for transmitting the PUSCH may precede a resource mapped tothe second UCI. For example, the first UCI may be mapped to a symbolimmediately before a DMRS symbol for transmitting a DMRS among aplurality of symbols forming the resources for transmitting the PUSCH,and the second UCI may be mapped to a symbol immediately after the DMRSsymbol.

This mapping method has an advantage in that a base station decodes theCGU-UCI first and can use information on the NR UCI or the payload sizeof the NR UCI included therein to decode the rest of the CGU-PUSCH. ThisCGU-UCI mapping method can also be applied when the NR UCI is notpiggybacked on the CGU-PUSCH.

When the NR UCI is piggybacked on the CGU-PUSCH and transmittedtogether, the mapping method illustrated in FIG. 27 may be applied inthe last DMRS symbol. That is, the CGU-UCI may be mapped to from asymbol positioned immediately on the left of the last DMRS symbol, andthe NR UCI may be mapped to from a symbol positioned immediately on theright of the last DMRS symbol in the frequency-first manner.

Likewise, accordingly this mapping method, a base station can decode theCGU-UCI first to identify a UE, or can know information, such as thepayload size of an HARQ-ACK of the NR UCI when information about the NRUCI is included in the CGU-UCI, thus being useful to decode theremaining part of the CGU-PUSCH.

Further, when the NR UCI is piggybacked on the CGU-PUSCH, NR UCI may bemapped, reserving the number of resource elements (RE) to be mapped tothe CGU-UCI. That is, when calculating the number of REs to be mapped toeach piece of NR UCI through a from the total number of REs availablefor the CGU-PUSCH, the quantity of REs to be mapped to the NR UCI may becalculated by excluding the number of REs for the CGU-UCI in advance.

It is assumed that X is the number of REs for the CGU-UCI. In thefollowing equation for calculating the quantity of REs to be mapped tothe NR UCI (HARQ-ACK), the number of REs for the CGU-UCI may be reservedby subtracting X from the total number of REs available for theCGU-PUSCH, after which the number of REs to be mapped to the HARQ-ACK,which is the NR UCI, may be calculated. The quantity of REs to be mappedmay be calculated by sequentially applying the same method to NR UCI,such as other CSI part I and/or CSI part II. The quantity of REs to bemapped to CSI part I may be calculated by excluding the quantity of REsto be mapped to the CGU-UCI and the HARQ-ACK from the total quantity ofREs for the CGU-PUSCH.

This can be expressed as the following equation.

$\begin{matrix}{Q_{ACK}^{\prime} = {\min\left\{ {\left\lceil \frac{\left( {O_{ACK} + L_{ACK}} \right) \cdot \beta_{offset}^{PUSCH} \cdot {\sum\limits_{l = 0}^{N_{{symb},{all}}^{PUSCH} - 1}\;{M_{sc}^{UCI}(l)}}}{\sum\limits_{r = 0}^{C_{{UL} - {SCH}} - 1}\; K_{r}} \right\rceil,{\left\lceil {\alpha \cdot {\sum\limits_{l = l_{0}}^{N_{{symb},{all}}^{PUSCH} - 1}\;{M_{sc}^{UCI}(l)}}} \right\rceil - X}} \right\}}} & \left\lbrack {{Equation}\mspace{14mu} 1} \right\rbrack\end{matrix}$

In the above equation, O_(ACK) denotes the number of HARQ-ACK bits,where when O_(ACK) is 360 or greater LACK is 11, and otherwise, LACK isthe number of CRC bits. M^(PUSCH) _(sc) denotes the number of scheduledband (subcarriers) for PUSCH transmission, N^(PUSCH) _(symb,all) denotesthe total number of OFDM symbols for PUSCH transmission (including OFDMsymbols used for a DMRS), β^(PUSCH) _(offset) denotes β^(HARQ-ACK)_(offset), C_(UL-SCH) denotes the number of code blocks for a UL-SCH forPUSCH transmission, K_(r) denotes the size of an rth code block for aUL-SCH for PUSCH transmission, and M^(UCI) _(sc)(l) denotes the numberof resource elements available for UCI transmission in OFDM symbol l. αis a value set through a higher-layer signal (parameter), such as an RRCsignal. X denotes the number of resource elements (REs) for CGU-UCI. l₀denotes the symbol index of a first OFDM symbol that does not carry DMRSof the PUSCH, after a first DMRS symbol, in the PUSCH transmission.

[Proposed method #8] Rate matching method in the case where a CGU-PUSCHor (periodic or semi-static) PUCCH resource overlaps with a dynamic ULscheduling resource or is within an interval of X symbols from a DLsignal/channel transmission resource.

Here, dynamic UL scheduling may refer to a dynamic PRACH or PUCCHresource indicated through (group) common DCI, and a DL signal/channelmay refer to an SSB, a CSI-RS (e.g., for measurement or beammanagement), paging/RMSI/OSI, or the like.

(1) When (partially) overlapping with a (candidate) resource, aCGU-PUSCH or a (periodic or semi-static) PUCCH may be dropped.

(2) When (partially) overlapping with a (candidate) resource, aCGU-PUSCH or a (periodic or semi-static) PUCCH may be transmitted(punctured or rate-matched) through some resources therefor, and thetime/frequency region of the resource used for the transmission may besignaled.

The content of the present disclosure is not limited to directcommunication between UEs and may be used for an uplink or downlink.Here, a base station or a relay node may employ the foregoing proposedmethods.

Examples of the above-described proposed methods may also be included asone of the implementation methods of the present disclosure. And,therefore, it is an evident fact that the above-described examples canbe understood as a type of proposed methods. Additionally, although theabove-described proposed methods can be implemented independently, themethod may also be implemented as a combined (or integrated) form ofpart of the proposed methods. For the information on the application ornon-application of the proposed methods (or information on the rules ofthe proposed methods), a rule may be defined so that the information canbe notified through a signal (e.g., a physical layer signal or a higherlayer signal), which is predefined by the base station to the UE or by atransmitting UE to a receiving UE.

FIG. 28 is a block diagram showing components of a transmitting device1810 and a receiving device 1820 for implementing the presentdisclosure. Here, the transmitting device and the receiving device maybe a base station and a terminal.

The transmitting device 1810 and the receiving device 1820 mayrespectively include transceivers 1812 and 1822 capable of transmittingor receiving radio frequency (RF) signals carrying information, data,signals and messages, memories 1813 and 1823 for storing various typesof information regarding communication in a wireless communicationsystem, and processors 1811 and 1821 connected to components such as thetransceivers 1812 and 1822 and the memories 1813 and 1823 and configuredto control the memories 1813 and 1823 and/or the transceivers 1812 and1822 such that the corresponding devices perform at least one ofembodiments of the present disclosure.

The memories 1813 and 1823 can store programs for processing and controlof the processors 1811 and 1821 and temporarily store input/outputinformation. The memories 1813 and 1823 may be used as buffers.

The processors 1811 and 1821 generally control overall operations ofvarious modules in the transmitting device and the receiving device.Particularly, the processors 1811 and 1821 can execute various controlfunctions for implementing the present disclosure. The processors 1811and 1821 may be referred to as controllers, microcontrollers,microprocessors, microcomputers, etc. The processors 1811 and 1821 canbe realized by hardware, firmware, software or a combination thereof.When the present disclosure is realized using hardware, the processors1811 and 1821 may include ASICs (application specific integratedcircuits), DSPs (digital signal processors), DSPDs (digital signalprocessing devices), PLDs (programmable logic devices), FPGAs (fieldprogrammable gate arrays) or the like configured to implement thepresent disclosure. When the present disclosure is realized usingfirmware or software, the firmware or software may be configured toinclude modules, procedures or functions for performing functions oroperations of the present disclosure, and the firmware or softwareconfigured to implement the present disclosure may be included in theprocessors 1811 and 1821 or stored in the memories 1813 and 1823 andexecuted by the processors 1811 and 1821.

The processor 1811 of the transmitting device 1810 can performpredetermined coding and modulation on a signal and/or data to betransmitted to the outside and then transmit the signal and/or data tothe transceiver 1812. For example, the processor 1811 can performdemultiplexing, channel coding, scrambling and modulation on a datastring to be transmitted to generate a codeword. The codeword caninclude information equivalent to a transport block which is a datablock provided by an MAC layer. One transport block (TB) can be codedinto one codeword. Each codeword can be transmitted to the receivingdevice through one or more layers. The transceiver 1812 may include anoscillator for frequency up-conversion. The transceiver 1812 may includeone or multiple transmission antennas.

The signal processing procedure of the receiving device 1820 may bereverse to the signal processing procedure of the transmitting device1810. The transceiver 1822 of the receiving device 1820 can receive RFsignals transmitted from the transmitting device 1810 under the controlof the processor 1821. The transceiver 1822 may include one or multiplereception antennas. The transceiver 1822 can frequency-down-convertsignals received through the reception antennas to restore basebandsignals. The transceiver 1822 may include an oscillator for frequencydown conversion. The processor 1821 can perform decoding anddemodulation on RF signals received through the reception antennas torestore data that is intended to be transmitted by the transmittingdevice 1810.

The transceivers 1812 and 1822 may include one or multiple antennas. Theantennas can transmit signals processed by the transceivers 1812 and1822 to the outside or receive RF signals from the outside and deliverthe RF signal to the transceivers 1812 and 1822 under the control of theprocessors 1811 and 1821 according to an embodiment of the presentdisclosure. The antennas may be referred to as antenna ports. Eachantenna may correspond to one physical antenna or may be configured by acombination of a plurality of physical antenna elements. A signaltransmitted from each antenna cannot be decomposed by the receivingdevice 1820. A reference signal (RS) transmitted corresponding to anantenna defines an antenna from the viewpoint of the receiving device1820 and can allow the receiving device 1820 to be able to estimate achannel with respect to the antenna irrespective of whether the channelis a single radio channel from a physical antenna or a composite channelfrom a plurality of physical antenna elements including the antenna.That is, an antenna can be defined such that a channel carrying a symbolon the antenna can be derived from the channel over which another symbolon the same antenna is transmitted. A transceiver which supports amulti-input multi-output (MIMO) function of transmitting and receivingdata using a plurality of antennas may be connected to two or moreantennas.

FIG. 29 illustrates an example of a signal processing module structurein the transmitting device 1810. Here, signal processing can beperformed by a processor of a base station/terminal, such as theprocessors 1811 and 1821 of FIG. 28 .

Referring to FIG. 29 , the transmitting device 1810 included in aterminal or a base station may include scramblers 301, modulators 302, alayer mapper 303, an antenna port mapper 304, resource block mappers 305and signal generators 306.

The transmitting device 1810 can transmit one or more codewords. Codedbits in each codeword are scrambled by the corresponding scrambler 301and transmitted over a physical channel. A codeword may be referred toas a data string and may be equivalent to a transport block which is adata block provided by the MAC layer.

Scrambled bits are modulated into complex-valued modulation symbols bythe corresponding modulator 302. The modulator 302 can modulate thescrambled bits according to a modulation scheme to arrangecomplex-valued modulation symbols representing positions on a signalconstellation. The modulation scheme is not limited and m-PSK (m-PhaseShift Keying) or m-QAM (m-Quadrature Amplitude Modulation) may be usedto modulate the coded data. The modulator may be referred to as amodulation mapper.

The complex-valued modulation symbols can be mapped to one or moretransport layers by the layer mapper 303. Complex-valued modulationsymbols on each layer can be mapped by the antenna port mapper 304 fortransmission on an antenna port.

Each resource block mapper 305 can map complex-valued modulation symbolswith respect to each antenna port to appropriate resource elements in avirtual resource block allocated for transmission. The resource blockmapper can map the virtual resource block to a physical resource blockaccording to an appropriate mapping scheme. The resource block mapper305 can allocate complex-valued modulation symbols with respect to eachantenna port to appropriate subcarriers and multiplex the complex-valuedmodulation symbols according to a user.

Each signal generator 306 can modulate complex-valued modulation symbolswith respect to each antenna port, that is, antenna-specific symbols,according to a specific modulation scheme, for example, OFDM (OrthogonalFrequency Division Multiplexing), to generate a complex-valued timedomain OFDM symbol signal. The signal generator can perform IFFT(Inverse Fast Fourier Transform) on the antenna-specific symbols, and aCP (cyclic Prefix) can be inserted into time domain symbols on whichIFFT has been performed. OFDM symbols are subjected to digital-analogconversion and frequency up-conversion and then transmitted to thereceiving device through each transmission antenna. The signal generatormay include an IFFT module, a CP inserting unit, a digital-to-analogconverter (DAC) and a frequency upconverter.

FIG. 30 illustrates another example of the signal processing modulestructure in the transmitting device 1810. Here, signal processing canbe performed by a processor of a terminal/base station, such as theprocessors 1811 and 1821 of FIG. 28 .

Referring to FIG. 30 , the transmitting device 1810 included in aterminal or a base station may include scramblers 401, modulators 402, alayer mapper 403, a precoder 404, resource block mappers 405 and signalgenerators 406.

The transmitting device 1810 can scramble coded bits in a codeword bythe corresponding scrambler 401 and then transmit the scrambled codedbits through a physical channel.

Scrambled bits are modulated into complex-valued modulation symbols bythe corresponding modulator 402. The modulator can modulate thescrambled bits according to a predetermined modulation scheme to arrangecomplex-valued modulation symbols representing positions on a signalconstellation. The modulation scheme is not limited and pi/2-BPSK(pi/2-Binary Phase Shift Keying), m-PSK (m-Phase Shift Keying) or m-QAM(m-Quadrature Amplitude Modulation) may be used to modulate the codeddata.

The complex-valued modulation symbols can be mapped to one or moretransport layers by the layer mapper 403.

Complex-valued modulation symbols on each layer can be precoded by theprecoder 404 for transmission on an antenna port. Here, the precoder mayperform transform precoding on the complex-valued modulation symbols andthen perform precoding. Alternatively, the precoder may performprecoding without performing transform precoding. The precoder 404 canprocess the complex-valued modulation symbols according to MIMO usingmultiple transmission antennas to output antenna-specific symbols anddistribute the antenna-specific symbols to the corresponding resourceblock mapper 405. An output z of the precoder 404 can be obtained bymultiplying an output y of the layer mapper 403 by an N*M precodingmatrix W. Here, N is the number of antenna ports and M is the number oflayers.

Each resource block mapper 405 maps complex-valued modulation symbolswith respect to each antenna port to appropriate resource elements in avirtual resource block allocated for transmission.

The resource block mapper 405 can allocate complex-valued modulationsymbols to appropriate subcarriers and multiplex the complex-valuedmodulation symbols according to a user.

Each signal generator 406 can modulate complex-valued modulation symbolsaccording to a specific modulation scheme, for example, OFDM, togenerate a complex-valued time domain OFDM symbol signal. The signalgenerator 406 can perform IFFT (Inverse Fast Fourier Transform) onantenna-specific symbols, and a CP (cyclic Prefix) can be inserted intotime domain symbols on which IFFT has been performed. OFDM symbols aresubjected to digital-analog conversion and frequency up-conversion andthen transmitted to the receiving device through each transmissionantenna. The signal generator 406 may include an IFFT module, a CPinserting unit, a digital-to-analog converter (DAC) and a frequencyupconverter.

The signal processing procedure of the receiving device 1820 may bereverse to the signal processing procedure of the transmitting device.Specifically, the processor 1821 of the transmitting device 1810 decodesand demodulates RF signals received through antenna ports of thetransceiver 1822. The receiving device 1820 may include a plurality ofreception antennas, and signals received through the reception antennasare restored to baseband signals, and then multiplexed and demodulatedaccording to MIMO to be restored to a data string intended to betransmitted by the transmitting device 1810. The receiving device 1820may include a signal restoration unit which restores received signals tobaseband signals, a multiplexer for combining and multiplexing receivedsignals, and a channel demodulator for demodulating multiplexed signalstrings into corresponding codewords. The signal restoration unit, themultiplexer and the channel demodulator may be configured as anintegrated module or independent modules for executing functionsthereof. More specifically, the signal restoration unit may include ananalog-to-digital converter (ADC) for converting an analog signal into adigital signal, a CP removal unit which removes a CP from the digitalsignal, an FET module for applying FFT (fast Fourier transform) to thesignal from which the CP has been removed to output frequency domainsymbols, and a resource element demapper/equalizer for restoring thefrequency domain symbols to antenna-specific symbols. Theantenna-specific symbols are restored to transport layers by themultiplexer and the transport layers are restored by the channeldemodulator to codewords intended to be transmitted by the transmittingdevice.

FIG. 31 illustrates an example of a wireless communication deviceaccording to an implementation example of the present disclosure.

Referring to FIG. 31 , the wireless communication device, for example, aterminal may include at least one of a processor 2310 such as a digitalsignal processor (DSP) or a microprocessor, a transceiver 2335, a powermanagement module 2305, an antenna 2340, a battery 2355, a display 2315,a keypad 2320, a global positioning system (GPS) chip 2360, a sensor2365, a memory 2330, a subscriber identification module (SIM) card 2325,a speaker 2345 and a microphone 2350. A plurality of antennas and aplurality of processors may be provided.

The processor 2310 can implement functions, procedures and methodsdescribed in the present description. The processor 2310 in FIG. 31 maybe the processors 1811 and 1821 in FIG. 28 .

The memory 2330 is connected to the processor 2310 and storesinformation related to operations of the processor. The memory may belocated inside or outside the processor and connected to the processorthrough various techniques such as wired connection and wirelessconnection. The memory 2330 in FIG. 31 may be the memories 1813 and 1823in FIG. 28 .

A user can input various types of information such as telephone numbersusing various techniques such as pressing buttons of the keypad 2320 oractivating sound using the microphone 2350. The processor 2310 canreceive and process user information and execute an appropriate functionsuch as calling using an input telephone number. In some scenarios, datacan be retrieved from the SIM card 2325 or the memory 2330 to executeappropriate functions. In some scenarios, the processor 2310 can displayvarious types of information and data on the display 2315 for userconvenience.

The transceiver 2335 is connected to the processor 2310 and transmitand/or receive RF signals. The processor can control the transceiver inorder to start communication or to transmit RF signals including varioustypes of information or data such as voice communication data. Thetransceiver includes a transmitter and a receiver for transmitting andreceiving RF signals. The antenna 2340 can facilitate transmission andreception of RF signals. In some implementation examples, when thetransceiver receives an RF signal, the transceiver can forward andconvert the signal into a baseband frequency for processing performed bythe processor. The signal can be processed through various techniquessuch as converting into audible or readable information to be outputthrough the speaker 2345. The transceiver in FIG. 31 may be thetransceivers 1812 and 1822 in FIG. 28 .

Although not shown in FIG. 31 , various components such as a camera anda universal serial bus (USB) port may be additionally included in theterminal. For example, the camera may be connected to the processor2310.

FIG. 31 is an example of implementation with respect to the terminal andimplementation examples of the present disclosure are not limitedthereto. The terminal need not essentially include all the componentsshown in FIG. 31 . That is, some of the components, for example, thekeypad 2320, the GPS chip 2360, the sensor 2365 and the SIM card 2325may not be essential components. In this case, they may not be includedin the terminal.

FIG. 32 illustrates an example of a 5G usage scenario to which thetechnical features of the present disclosure are applicable. The 5Gusage scenario illustrated in FIG. 32 is merely for illustrativepurposes, and the technical features of the present disclosure may alsobe applied to other 5G usage scenarios which are not shown in FIG. 32 .

Referring to FIG. 32 , three major areas required for 5G includes: (1)an enhanced mobile broadband (eMBB) area; (2) a massive machine-typecommunication (mMTC) area; and 3) an ultra-reliable and low-latencycommunication (URLLC) area. Some use cases may require a plurality ofareas for optimization, and other use cases may focus on only one keyperformance indicator (KPI). 5G supports these various use cases in aflexible and reliable manner.

eMBB focuses on overall improvement in data rate, latency, user density,and capacity and coverage of mobile broadband connection. eMBB is aimedat a throughput of about 10 Gbps. eMBB further surpasses basic mobileInternet access and covers abundant interactive operations, a cloud, andmedia and entertainment applications in augmented reality. Data is onekey driver in 5G, and dedicated voice services may not be provided forthe first time in the 5G era. In 5G, a voice is expected to be processedas an application simply using data connection provided by acommunication system. Main reasons for an increase in the amount oftraffic are an increase in the size of content and a growing number ofapplications requiring a high data rate. Streaming services (audio andvideo) and interactive video and mobile Internet connectivity will bewidely used as more devices are connected to the Internet. A largenumber of applications require always-on connectivity in order to pushreal-time information and notifications to a user. Cloud storage andapplications are rapidly growing in use on mobile communicationplatforms and can be applied to both work and entertainment. Cloudstorage is a special use case which contributes to an increase in uplinkdata rate. 5G is also used for telebusiness on the cloud, and requiresmuch lower end-to-end latency to maintain a satisfactory user experiencewhen a tactile interface is used. In entertainments, for example, cloudgames and video streaming are other key factors that require enhancedmobile broadband capabilities. Entertainments are essential forsmartphones and tablet PCs in any place including a high-mobilityenvironment, such as a train, a car, and an airplane. Another use caseis augmented reality and information retrieval for entertainments. Here,augmented reality requires very low latency and a large amount of datain a moment.

mMTC is designed to enable communication between a large number oflow-cost devices operated with a battery and is intended to supportsmart metering, distribution, work areas, and applications includingbody sensors. mMTC is aimed at supporting a battery life of about tenyears and/or about one million devices per square kilometer. mMTCenables seamless connection of embedded sensors in any field and is oneof the most widely used 5G applications. Potentially, the number of IoTdevices is expected to reach 20.4 billion by 2020. Industrial IoT is onefield where 5G plays a key role in enabling smart cities, assettracking, smart utilities, and agricultural and securityinfrastructures.

URLLC enables devices and machines to communicate with high reliability,very low latency, and high availability, thus being ideal for vehicularcommunications, industrial control, factory automation, remote surgery,a smart grid, and public safety applications. URLLC aims at a latency ofabout 1 ms. URLLC includes new services that will change the industrythrough remote control of key infrastructures andultra-reliable/low-latency links, such as self-driving vehicles.Reliability and latency levels are essential for smart grid control,industrial automation, robotics, and drone control and coordination.

Next, a plurality of use cases included in the triangle of FIG. 32 willbe described in more detail.

5G is a technique for providing a stream rated at hundreds of megabitsper second to gigabytes per second and can complement fiber-to-the-home(FTTH) and cable-based broadband (or DOCSIS). This high speed may berequired to provide not only virtual reality (VR) and augmented reality(AR) but also a TV with a resolution of 4K or higher (6K, 8K or above).VR and AR applications mostly include immersive sporting events. Aparticular application may require a special network configuration. Forexample, for a VR game, a game company may need to integrate a coreserver with an edge network server of a network operator in order tominimize latency.

An automotive area is expected to be an important new driver for 5G withmany uses for vehicular mobile communications. For example,entertainments for passengers require both high-capacity andhigh-mobility broadband, because future users continue to expecthigh-quality connection regardless of location and speed thereof.Another use case in the automotive area is an AR dashboard. A driver canidentify an object in the dark on what is being viewed through a frontwindow through the AR dashboard. The AR dashboard displays informationto be informed to the driver about the distance and movement of anobject in an overlapping manner. In the future, a wireless moduleenables communication between vehicles, information exchange between avehicle and a supporting infrastructure, and information exchangebetween a vehicle and a different connected device (e.g., a deviceaccompanied by a pedestrian). A safety system provides an alternativecourse for an action so that a driver can drive safely, thereby reducingthe risk of accidents. The next step would be a remote control vehicleor a self-driving vehicle, which requires highly reliable and very fastcommunication between different self-driving vehicles and/or between avehicle and an infrastructure. In the future, a self-driving vehiclewill perform all driving activities, and the driver will focus only on atraffic problem that the vehicle cannot autonomously identify. Technicalrequirements of self-driving vehicles are ultra-low latency, high speed,and high reliability to increase traffic safety to the extent thathumans cannot achieve.

In a smart city and a smart home, which are referred to as a smartsociety, a high-density wireless sensor network will be embedded. Adistributed network of intelligent sensors will identify conditions forcost and energy-efficient maintenance of a city or house. Similarsettings may be established for each home. A temperature sensor, windowand heating controllers, a security system, and home appliances are allwirelessly connected. Many of these sensors typically require low datarate, low power, and low cost. However, for example, a real-time HDvideo may be required for a particular type of a device for monitoring.

Since consumption and distribution of energy including heat or gas isdecentralized to a high degree, automated control of a distributedsensor network is required. A smart grid collects information andinterconnects sensors using digital information and communicationtechnology to function according to the information. This informationmay include supplier and consumer behavior, thus enabling the smart gridto improve the distribution of fuel, such as electricity, in efficient,reliable, economical, production-sustainable, and automated manners. Thesmart grid may be considered as a sensor network having low latency.

The health sector has a large number of applications that can benefitfrom mobile communications. Communication systems can supporttelemedicine to provide clinical care in remote locations. Telemedicinecan help to reduce a distance barrier and can improve access to medicalservices that are not continuously available in distant rural areas.Telemedicine is also used to save lives in critical treatment andemergency situations. A wireless sensor network based on mobilecommunication can provide remote monitoring and sensors for parameters,such as heart rate and blood pressure.

Wireless and mobile communication is gradually becoming important inindustrial applications. Wiring involves high costs for installation andmaintenance. Thus, the possibility of replacing a cable with areconfigurable wireless link is an attractive aspect for differentindustrial fields. However, to replace a cable with a reconfigurablewireless link, a wireless connection needs to operate with similarlatency, reliability, and capacity to those of a cable and needs to bemanaged in a simplified manner. Low latency and a very low errorprobability are new requirements for a 5G connection.

Logistics and cargo tracking is an important use case for mobilecommunication which enables the tracking of inventory and packagesanywhere using a location-based information system. The use case oflogistics and cargo tracking typically requires low data rate but needsa large range and reliable location information.

<Artificial Intelligence (AI)>

Artificial intelligence refers to a field of study on artificialintelligence or methodologies for creating artificial intelligence, andmachine learning refers to a field of study on methodologies fordefining and solving various issues in the area of artificialintelligence. Machine learning is also defined as an algorithm forimproving the performance of an operation through steady experiences ofthe operation.

An artificial neural network (ANN) is a model used in machine learningand may refer to an overall problem-solving model that includesartificial neurons (nodes) forming a network by combining synapses. Theartificial neural network may be defined by a pattern of connectionbetween neurons of different layers, a learning process of updating amodel parameter, and an activation function generating an output value.

The artificial neural network may include an input layer, an outputlayer, and optionally one or more hidden layers. Each layer includes oneor more neurons, and the artificial neural network may include synapsesthat connect neurons. In the artificial neural network, each neuron mayoutput a function value of an activation function of input signals inputthrough a synapse, weights, and deviations.

A model parameter refers to a parameter determined through learning andincludes a weight of synapse connection and a deviation of a neuron. Ahyperparameter refers to a parameter to be set before learning in amachine learning algorithm and includes a learning rate, the number ofiterations, a mini-batch size, and an initialization function.

Learning an artificial neural network may be intended to determine amodel parameter for minimizing a loss function. The loss function may beused as an index for determining an optimal model parameter in a processof learning the artificial neural network.

Machine learning may be classified into supervised learning,unsupervised learning, and reinforcement learning.

Supervised learning refers to a method of training an artificial neuralnetwork with a label given for learning data, wherein the label mayindicate a correct answer (or result value) that the artificial neuralnetwork needs to infer when the learning data is input to the artificialneural network. Unsupervised learning may refer to a method of trainingan artificial neural network without a label given for learning data.Reinforcement learning may refer to a training method for training anagent defined in an environment to choose an action or a sequence ofactions to maximize a cumulative reward in each state.

Machine learning implemented with a deep neural network (DNN) includinga plurality of hidden layers among artificial neural networks isreferred to as deep learning, and deep learning is part of machinelearning. Hereinafter, machine learning is construed as including deeplearning.

<Robot>

Robots may refer to machinery that automatically process or operate agiven task with own ability thereof. In particular, a robot having afunction of recognizing an environment and autonomously making ajudgment to perform an operation may be referred to as an intelligentrobot.

Robots may be classified into industrial, medical, household, militaryrobots and the like according uses or fields.

A robot may include an actuator or a driver including a motor to performvarious physical operations, such as moving a robot joint. In addition,a movable robot may include a wheel, a brake, a propeller, and the likein a driver to run on the ground or fly in the air through the driver.

<Self-Driving or Autonomous Driving>

Autonomous driving refers to a technique of self-driving, and anautonomous vehicle refers to a vehicle that travels without a user'soperation or with a user's minimum operation of a user.

For example, autonomous driving may include a technique for maintaininga lane while driving, a technique for automatically adjusting speed,such as adaptive cruise control, a technique for automatically travelingalong a predetermined route, and a technique for traveling byautomatically setting a route when a destination is set.

A vehicle may include a vehicle having only an internal combustionengine, a hybrid vehicle having both an internal combustion engine andan electric motor, and an electric vehicle having only an electricmotor, and may include not only an automobile but also a train, amotorcycle, and the like.

An autonomous vehicle can be regarded as a robot having an autonomousdriving function.

<Extended Reality (XR)>

Extended reality collectively refers to virtual reality (VR), augmentedreality (AR), and mixed reality (MR). VR technology is a computergraphic technology of providing a real-world object and background onlyin a CG image, AR technology is a computer graphic technology ofproviding a virtual CG image on a real object image, and MR technologyis a computer graphic technology of providing virtual objects mixed andcombined with the real world.

MR technology is similar to AR technology in that a real object and avirtual object are displayed together. However, a virtual object is usedas a supplement to a real object in AR technology, whereas a virtualobject and a real object are used as equal statuses in MR technology.

XR technology may be applied to a head-mount display (HMD), a head-updisplay (HUD), a cellular phone, a tablet PC, a laptop computer, adesktop computer, a TV, digital signage, and the like. A device to whichXR technology is applied may be referred to as an XR device.

FIG. 33 illustrates an AI device 100.

The AI device 100 may be configured as a stationary device or a movabledevice, such as a TV, a projector, a cellular phone, a smartphone, adesktop computer, a laptop computer, a digital broadcasting terminal, apersonal digital assistant (PDA), a portable multimedia player (PMP), anavigation system, a tablet PC, a wearable device, a set-top box (STB),a DMB receiver, a radio, a washing machine, a refrigerator, a desktopcomputer, digital signage, a robot, or a vehicle.

Referring to FIG. 33 , the terminal 100 may include a communication unit110, an input unit 120, a learning processor 130, a sensing unit 140, anoutput unit 150, a memory 170, and a processor 180.

The communication unit 110 may transmit and receive data to and fromexternal devices, such as other AI devices 100 a to 100 e and an AIserver 200, using wired or wireless communication technology. Forexample, the communication unit 110 may transmit and receive sensorinformation, a user input, a learning model, and a control signal, forexample, to and from external devices.

Here, communication technology used by the communication unit 110 maybe, for example, a global system for mobile communication (GSM), codedivision multiple access (CDMA), long-term evolution (LTE), 5G, wirelessLAN (WLAN), wireless-fidelity (Wi-Fi), Bluetooth™, radio frequencyidentification (RFID), infrared data association (IrDA), ZigBee, ornear-field communication (NFC).

The input unit 120 may acquire various types of data.

Here, the input unit 120 may include a camera to input an image signal,a microphone to receive an audio signal, and a user input unit toreceive information input from a user. Here, the camera or themicrophone may be considered as a sensor, and a signal acquired from thecamera or the microphone may be referred to as sensing data or sensorinformation.

The input unit 120 may acquire input data to be used when acquiring anoutput using learning data for model learning and a learning model. Theinput unit 120 may acquire unprocessed input data, in which case theprocessor 180 or the learning processor 130 may extract an input featureby preprocessing the input data.

The learning processor 130 may train a model configured with anartificial neural network using the learning data. Here, the trainedartificial neural network may be called a learning model. The learningmodel may be used to infer a result value for newly input data otherthan the learning data, and the inferred value may be used as adetermination base for performing any operation.

Here, the learning processor 130 may perform AI processing along with alearning processor 240 of an AI server 200.

Here, the learning processor 130 may include a memory integrated with orconfigured the in AI device 100. Alternatively, the learning processor130 may be configured using the memory 170, an external memory directlycoupled to the AI device 100, or a memory retained in an externaldevice.

The sensing unit 140 may acquire at least one of internal information onthe AI device 100 and surrounding environmental information and userinformation on the AI device 100 using various sensors.

Here, the sensors included in the sensing unit 140 may include aproximity sensor, an illuminance sensor, an acceleration sensor, amagnetic sensor, a gyro sensor, an inertial sensor, an RGB sensor, an IRsensor, a fingerprint recognition sensor, an ultrasonic sensor, anoptical sensor, a microphone, lidar, and radar.

The output unit 150 may generate a visual output, an auditory output, ora tactile output.

Here, the output unit 150 may include a display to output visualinformation, a speaker to output auditory information, and a hapticmodule to output tactile information.

The memory 170 may store data which assists various functions of the AIdevice 100. For example, memory 170 may store input data acquired by theinput unit 120, learning data, a learning model, and a learning history.

The processor 180 may determine at least one executable operation of theAI device 100 based on information determined or generated using a dataanalysis algorithm or a machine learning algorithm. The processor 180may control constituent elements of the AI device 100 to perform thedetermined operation.

To this end, the processor 180 may request, retrieve, receive, orutilize data of the learning processor 130 or the memory 170 and maycontrol the constituent elements of the AI device 100 to execute apredictable operation or an operation that is determined desirable amongthe at least one executable operation.

When connection of an external device is necessary to perform thedetermined operation, the processor 180 may generate a control signal tocontrol the external device and may transmit the generated controlsignal to the external device.

The processor 180 may acquire intent information corresponding to a userinput and may determine a requirement of a user based on the acquiredintent information.

Here, the processor 180 may acquire the intent information correspondingto the user input using at least one of a speech-to-text (STT) enginefor converting a voice input into a character string and a naturallanguage processing (NLP) engine for acquiring intent information of anatural language.

Here, at least one of the STT engine or the NLP engine may be at leastpartially configured with an artificial neural network learned accordingto a machine learning algorithm. Further, at least one of the STT engineor the NLP engine may be learned by the learning processor 130, may belearned by the learning processor 240 of the AI server 200, or may belearned by distributed processing of the learning processors 130 and240.

The processor 180 may collect history information including the contentof an operation of the AI device 100 or feedback on an operation fromthe user and may store the collected history information in the memory170 or the learning processor 130 or may transmit the collected historyinformation to an external device, such as the AI server 200. Thecollected history information may be used to update a learning model.

The processor 180 may control at least some of the constituent elementsof the AI device 100 in order to drive an application program stored inthe memory 170. Further, the processor 180 may operate two or more ofthe constituent elements of the AI device 100 in combination in order todrive the application program.

FIG. 34 illustrates an AI server 200 according to an embodiment of thepresent disclosure.

Referring to FIG. 34 , the AI server 200 may refer to a device thattrains an artificial neural network using a machine learning algorithmor uses the trained artificial neural network. The AI server 200 may beconfigured with a plurality of servers to perform distributed processingand may be defined as a 5G network. The AI server 200 may be included asa constituent element of an AI device 100 to perform at least part of AIprocessing together with the AI device 100.

The AI server 200 may include a communication unit 210, a memory 230, alearning processor 240, and a processor 260.

The communication unit 210 may transmit and receive data to and from anexternal device, such as the AI device 100.

The memory 230 may include a model storage unit 231. The model storageunit 231 may store a model (or an artificial neural network) 231 a whichis being learned or has been learned through the learning processor 240.

The learning processor 240 may train the artificial neural network 231 ausing learning data. A learning model may be used, being mounted in theAI server 200 of the artificial neural network or being mounted in anexternal device, such as the AI device 100.

The learning model may be configured in hardware, software, or acombination of hardware and software. When the learning model ispartially or entirely configured in software, one or more instructionsforming the learning model may be stored in the memory 230.

The processor 260 may infer a result value for newly input data usingthe learning model and may generate a response or a control commandbased on the inferred result value.

FIG. 35 illustrates an AI system 1.

Referring to FIG. 35 , in the AI system 1, at least one of an AI server200, a robot 100 a, a self-driving vehicle 100 b, an XR device 100 c, asmartphone 100 d, or a home appliance 100 e is connected with a cloudnetwork. Here, the robot 100 a, the self-driving vehicle 100 b, the XRdevice 100 c, the smartphone 100 d, or the home appliance 100 e to whichAI technology is applied may be referred to as an AI device 100 a to 100e.

The cloud network 10 may refer to a network that is a part of cloudcomputing infrastructure or exists in cloud computing infrastructure.Here, the cloud network 10 may be configured using a 3G network, a 4G orlong-term evolution (LTE) network, or a 5G network.

The devices 100 a to 100 e and 200 included in the AI system 1 may beconnected to each other through the cloud network 10. In particular, thedevices 100 a through 100 e and 200 may communicate with each otherthrough a base station and may also directly communicate with each otherwithout using a base station.

The AI server 200 may include a server performing AI processing and aserver performing an operation on big data.

The AI server 200 may be connected with at least one of the robot 100 a,the self-driving vehicle 100 b, the XR device 100 c, the smartphone 100d, and the home appliance 100 e, which are AI devices included in the AIsystem 1, via the cloud network 10 and may assist at least part of AIprocessing of the connected devices 100 a to 100 e.

The AI server 200 may train an artificial neural network according to amachine learning algorithm for the AI devices 100 a to 100 e, maydirectly store a learning model, or may transmit a learning model to theAI devices 100 a to 100 e.

The AI server 200 may receive input data from the AI devices 100 a to100 e, may infer a result value with respect to the received input datausing a learning model, may generate a response or a control command onthe basis of the inferred result value, and may transmit the response orthe control command to the AI devices 100 a to 100 e.

Alternatively, the AI devices 100 a to 100 e may directly infer a resultvalue with respect to input data using a learning model and may generatea response or a control command on the basis of the inferred resultvalue.

Hereinafter, various embodiments of the AI devices 100 a to 100 e towhich the foregoing technology is applied will be described. The AIdevices 100 a to 100 e illustrated in FIG. 2 may be considered asspecific examples of an AI device 100 illustrated in FIG. 3 .

<AI+Robot>

The robot 100 a may be configured, in combination with AI technology, asa guide robot, a carrying robot, a cleaning robot, a wearable robot, anentertainment robot, a pet robot, an unmanned aerial robot, or the like.

The robot 100 a may include a robot control module to control anoperation, and the robot control module may refer to a software moduleor a hardware chip to implement the software module.

The robot 100 a may acquire state information about the robot 100 a, maydetect (recognize) surroundings and an object, may generate map data,may determine a traveling route and a driving plan, may determine aresponse to a user interaction, or may determine an operation usingsensor information acquired from various types of sensors.

Here, the robot 100 a may use sensor information acquired from at leastone sensor among lidar, radar, and a camera in order to determine thetraveling route and the driving plan.

The robot 100 a may perform the foregoing operations using a learningmodel configured with at least one artificial neural network. Forexample, the robot 100 a may recognize surroundings and an object usingthe learning model and may determine an operation using information onthe recognized surroundings and or object. Here, the learning model maybe learned directly by the robot 100 a or may be learned from anexternal device, such as the AI server 200.

Here, the robot 100 a may perform the operations by directly producing aresult using the learning model, or may perform the operations bytransmitting sensor information to the external device, such as theserver 200, and receiving a result produced accordingly.

The robot 100 a may determine a traveling route and a driving plan usingat least one of the map data, object information detected from thesensor information, or object information acquired from the externaldevice and may control a driver to drive the robot 100 a according tothe determine traveling route and driving plan.

The map data may include object identification information on variousobjects disposed in a space where the robot 100 a travels. For example,the map data may include object identification information on stationaryobjects, such as a wall or a door, and movable objects, such as a potplant or a desk. The object identification information may include aname, a type, a distance, a position, or the like.

The robot 100 a may control the driver based on a user'scontrol/interaction, thereby operating or driving. Here, the robot 100 amay acquire intent information on an interaction according to the user'saction or utterance, may determine a response based on the acquiredintent information, and may operate accordingly.

<AI+Autonomous Driving>

The self-driving vehicle 100 b may be configured, in combination with AItechnology, as a mobile robot, a vehicle, an unmanned aircraft, or thelike.

The self-driving vehicle 100 b may include a self-driving control moduleto control a self-driving function, and the self-driving control modulemay refer to a software module or a hardware chip to implement thesoftware module. The self-driving control module may be included as acomponent in the self-driving vehicle 100 b, or may be configured asseparate hardware outside the self-driving vehicle 100 b and may beconnected thereto.

The self-driving vehicle 100 b may acquire state information about theself-driving vehicle 100 b, may detect (recognize) surroundings and anobject, may generate map data, may determine a traveling route and adriving plan, or may determine an operation using sensor informationacquired from various types of sensors.

Here, like the robot 100 a, the self-driving vehicle 100 b may usesensor information acquired from at least one sensor among lidar, radar,and a camera in order to determine the traveling route and the drivingplan.

In particular, the self-driving vehicle 100 b may recognize anenvironment or an object of a blind spot or an area over a certaindistance by receiving sensor information from external devices or mayreceive directly recognized information about the environment or theobject from external devices.

The self-driving vehicle 100 b may perform the foregoing operationsusing a learning model configured with at least one artificial neuralnetwork. For example, the self-driving vehicle 100 b may recognizesurroundings and an object using the learning model and may determine adriving route using information on the recognized surroundings and orobject. Here, the learning model may be learned directly by theself-driving vehicle 100 b or may be learned from an external device,such as the AI server 200.

Here, the self-driving vehicle 100 b may perform the operations bydirectly producing a result using the learning model, or may perform theoperations by transmitting sensor information to the external device,such as the server 200, and receiving a result produced accordingly.

The self-driving vehicle 100 b may determine a traveling route and adriving plan using at least one of the map data, object informationdetected from the sensor information, or object information acquiredfrom the external device and may control a driver to drive theself-driving vehicle 100 b according to the determine traveling routeand driving plan.

The map data may include object identification information on variousobjects disposed in a space (e.g., a road) where the self-drivingvehicle 100 b runs. For example, the map data may include objectidentification information on stationary objects, such as a streetlight,a rock, or a building, and movable objects, such as a vehicle or apedestrian. The object identification information may include a name, atype, a distance, a position, or the like.

The self-driving vehicle 100 b may control the driver based on a user'scontrol/interaction, thereby operating or driving. Here, theself-driving vehicle 100 b may acquire intent information on aninteraction according to the user's action or utterance, may determine aresponse based on the acquired intent information, and may operateaccordingly.

<AI+XR>

The XR device 100 c may be configured, in combination with AItechnology, as a head-mounted display (HMD), an in-vehicle head-updisplay (HUD), a television, a cellular phone, a smartphone, a computer,a wearable device, a home appliance, digital signage, a vehicle, astationary robot, or a mobile robot.

The XR device 100 c may analyze 3D point cloud data or image dataacquired via various sensors or from an external device to generateposition data and attribute data about 3D points, thereby obtaininginformation about a surrounding space or a real object, rendering an XRobject to output, and outputting the XR object. For example, the XRdevice 100 c may output an XR object including additional informationabout a recognized object in association with the recognized object.

The XR device 100 c may perform the foregoing operations using alearning model configured with at least one artificial neural network.For example, the XR device 100 c may recognize a real object from 3Dpoint cloud data or image data using the learning model and may provideinformation corresponding to the recognized real object. Here, thelearning model may be learned directly by the XR device 100 c or learnedfrom an external device, such as the AI server 200 a.

Here, the XR device 100 c may perform the operations by directlyproducing a result using the learning model, or may perform theoperations by transmitting sensor information to the external device,such as the server 200, and receiving a result produced accordingly.

<AI+Robot+Autonomous Driving>

The robot 100 a may be configured, in combination with AI technology andautonomous driving technology, as a guide robot, a carrying robot, acleaning robot, a wearable robot, an entertainment robot, a pet robot,an unmanned aerial robot, or the like.

The robot 100 a to which AI technology and autonomous driving technologyare applied may refer to a robot having an autonomous driving functionor the robot 100 a interacting with the self-driving vehicle 100 b.

The robot 100 a having the autonomous driving function collectivelyrefers to devices that autonomously move according to a given movingline without a user's control or autonomously determine a moving lineand moves accordingly.

The robot 100 a having the autonomous driving function and theself-driving vehicle 100 b may use a common sensing method in order todetermine at least one of a traveling route or a driving plan. Forexample, The robot 100 a having the autonomous driving function and theself-driving vehicle 100 b may determine at least one of a travelingroute or a driving plan using information sensed by lidar, radar, or acamera.

The robot 100 a interacting with the self-driving vehicle 100 b mayexist separately from the self-driving vehicle 100 b and may beassociated with the autonomous driving function inside or outside theself-driving vehicle 100 b or may perform an operation associated with auser riding in the self-driving vehicle 100 b.

Here, the robot 100 a interacting with the self-driving vehicle 100 bmay control or assist the autonomous driving function of theself-driving vehicle 100 b by acquiring sensor information instead ofthe self-driving vehicle 100 b and providing the sensor information tothe self-driving vehicle 100 b, or by acquiring sensor information,producing surrounding environment information or object information, andproviding these pieces of information to the self-driving vehicle 100 b.

Alternatively, the robot 100 a interacting with the self-driving vehicle100 b may control a function of the self-driving vehicle 100 b bymonitoring the user riding in the self-driving vehicle 100 b orinteracting with the user. For example, when it is determined that adriver feels sleepy, the robot 100 a may activate the autonomous drivingfunction of the self-driving vehicle 100 b or may assist control by thedriver of the self-driving vehicle 100 b. Here, the function of theself-driving vehicle 100 b controlled by the robot 100 a may include notonly the autonomous driving function but also a function provided by anavigation system or a stereo system provided in the self-drivingvehicle 100 b.

Alternatively, the robot 100 a interacting with the self-driving vehicle100 b may provide information or may assist a function for theself-driving vehicle 100 b outside the self-driving vehicle 100 b. Forexample, the robot 100 a may provide, like a smart traffic light,traffic information including signal information to the self-drivingvehicle 100 b or may interact, like an automatic electricity charger foran electric vehicle, with the self-driving vehicle 100 b toautomatically connect an electricity charger to a charging inlet.

<AI+Robot+XR>

The robot 100 a may be configured, in combination with AI technology andXR technology, as a guide robot, a carrying robot, a cleaning robot, awearable robot, an entertainment robot, a pet robot, an unmanned aerialrobot, a drone, or the like.

The robot 100 a to which XR technology is applied may refer to a robotto be controlled/to interact with in an XR image. In this case, therobot 100 a is distinguished from the XR device 100 c and may beconnected therewith.

When the robot 100 a to be controlled/to interact with in the XR imageacquires sensor information from sensors including a camera, the robot100 a or the XR device 100 c may generate an XR image based on thesensor information, and the XR device 100 c may output the generated XRimage. The robot 100 a may operate based on a control signal inputthrough the XR device 100 c or an interaction with a user.

For example, the user may identify an XR image corresponding to theviewpoint of the robot 100 a remotely connected through an externaldevice, such as the XR device 100 c, and may adjust an autonomousdriving route of the robot 100 a, may control an operation or driving ofthe robot 100 a, or may identify information on a neighboring objectthrough an interaction.

<AI+Autonomous Driving+XR>

The self-driving vehicle 100 b may be configured, in combination with AItechnology and XR technology, as a mobile robot, a vehicle, an unmannedaerial robot, or the like.

The self-driving vehicle 100 b to which XR technology is applied mayrefer to a self-driving vehicle having a device to provide an XR imageor a self-driving vehicle to be controlled/to interact with in an XRimage. In particular, the self-driving vehicle 100 b to be controlled/tointeract with in the XR image is distinguished from the XR device 100 cand may be connected therewith.

The self-driving vehicle 100 b having the device to provide the XR imagemay acquire sensor information from sensors including a camera and mayoutput an XR image generated based on the acquired sensor information.For example, the self-driving vehicle 100 b may include an HUD to outputan XR image, thereby providing a passenger with an XR objectcorresponding to a real object of an object on a screen.

Here, when the XR object is output on the HUD, at least part of the XRobject may be output to overlap with the real object at which thepassenger looks. However, when the XR object is output on a displayprovided in the self-driving vehicle 100 b, at least part of the XRobject may be output to overlap with an object on the screen. Forexample, the self-driving vehicle 100 b may output XR objectscorresponding to objects, such as a lane, another vehicle, a trafficlight, a traffic sign, a motorcycle, a pedestrian, a building, and thelike.

When the self-driving vehicle 100 b to be controlled/to interact with inthe XR image acquires sensor information from sensors including acamera, the self-driving vehicle 100 b or the XR device 100 c maygenerate an XR image based on the sensor information, and the XR device100 c may output the generated XR image. The self-driving vehicle 100 bmay operate based on a control signal input through the XR device 100 cor an interaction with a user.

Hereinafter, a channel coding scheme will be described.

Channel coding schemes according to some embodiments of the presentdisclosure may generally include a low-density parity-check (LDPC)coding scheme for data and a polar coding scheme for controlinformation.

A network/UE may perform LDPC coding on a PDSCH/PUSCH having two basegraphs (BGs). Here, BG1 may be related to a mother code rate of 1/3, andBG2 may be related to a mother code rate of 1/5.

For coding of control information, coding schemes, such as repetitioncoding/simplex coding/Reed-Muller coding, may be supported. The polarcoding scheme may be used when control information has a length longerthan 11 bits. A mother code size may be 512 for a downlink, and a mothercode size may be 1024 for an uplink. Coding scheme for uplink controlinformation may be summarized as in the following table.

TABLE 7 Uplink control information size including CRC, if presentChannel code 1 Repetition code 2 Simplex code 3-11 Reed-Muller code >11Polar code

The polar coding scheme may be used for a PBCH. This coding scheme maybe the same as that for a PDCCH.

Hereinafter, an LDPC coding structure will be described.

An LDPC code is a (n, k) linear block code defined by a sparseparity-check matrix H of a null-space of (n−k)×n.

An LDPC code applicable to some embodiments of the present disclosuremay be represented as follows.

$\begin{matrix}{{{Hx}^{T} = 0}{{Hx}^{T} = {{\begin{bmatrix}1 & 1 & 1 & 0 & 0 \\1 & 0 & 0 & 1 & 1 \\1 & 1 & 0 & 0 & 0 \\0 & 1 & 1 & 1 & 0\end{bmatrix}\begin{bmatrix}x_{1} \\x_{2} \\x_{3} \\x_{4} \\x_{5}\end{bmatrix}} = \begin{bmatrix}0 \\0 \\0 \\0\end{bmatrix}}}} & \left\lbrack {{Equation}\mspace{14mu} 2} \right\rbrack\end{matrix}$

FIG. 36 illustrates an example of a parity-check matrix expressed as aprotograph.

Specifically, FIG. 36 shows a parity-check matrix indicating acorrelation between a variable node and a check node, which is expressedas a protograph.

For example, referring to FIG. 36 , variable nodes v₁, v₂, v₃, v₄, v₆,and v₇ are correlated with check node c₁, and check nodes c₂, c₃, and c₄are correlated with variable node v8.

FIG. 37 illustrates an example of an encoder structure for a polar code.

Specifically, (a) of FIG. 37 shows an example of a base module of thepolar code, and (b) of FIG. 37 shows a base matrix.

The polar code is known as a code capable of acquiring channel capacityin a binary-input discrete memoryless channel (B-DMC). That is, when thesize N of a code block increases to infinity, channel capacity can beobtained.

FIG. 38 schematically illustrates an example of an encoder operation ofa polar code.

Referring to FIG. 38 , the encoder of the polar code may perform channelcombining and channel splitting. Specifically, the encoder of the polarcode may combine existing channels into one vector channel, or may splitone vector channel into a plurality of new channels. For example, theexisting channels before combining into one vector channel may beuniform, and the plurality of new channels into one vector channel issplit may be polarized.

<Discontinuous Reception (DRX)>

Discontinuous reception (DRX) refers to an operation mode that enables aUE to reduce battery consumption and to discontinuously receive adownlink channel. That is, the UE configured in DRX may discontinuouslyreceive a DL signal, thereby reducing power consumption.

A DRX operation is performed within a DRX cycle indicating a time periodin which an on duration is periodically repeated. The DRX cycle includesan on duration and a sleep duration (or opportunity for DRX). The onduration indicates a time period in which a UE monitors a PDCCH toreceive the PDCCH.

DRX may be performed in a radio resource control (RRC)_IDLE state (ormode), RRC_INACTIVE state (or mode), or RRC_CONNECTED state (or mode).In the RRC_IDLE state and the RRC_INACTIVE state, DRX may be used todiscontinuously receive a paging signal.

-   -   RRC_IDLE state: State in which a wireless connection (RRC        connection) is not established between a base station and a UE.    -   RRC_INACTIVE state: State in which a wireless connection (RRC        connection) is established between a base station and a UE but        is deactivated.    -   RRC_CONNECTED state: State in which a radio connection (RRC        connection) is established between a base station and a UE.

DRX may be basically divided into idle-mode DRX, connected DRX (C-DRX),and extended DRX.

DRX applied in the idle state may be referred to as idle-mode DRX, andDRX applied in the connected state may be referred to as connected-modeDRX (C-DRX).

Extended/enhanced DRX (eDRX) is a mechanism capable of extending thecycle of idle-mode DRX and C-DRX and may be mainly used for applicationof (massive) IoT. In idle-mode DRX, whether to allow eDRX may beconfigured based on system information (e.g., SIB1). SIB1 may include aneDRX-allowed parameter. The eDRX-allowed parameter is a parameterindicating whether idle-mode extended DRX is allowed.

<Idle-Mode DRX>

In the idle mode, a UE may use DRX to reduce power consumption. Onepaging occasion (PO) is a subframe in which a paging-radio networktemporary identifier (P-RNTI) can be transmitted through a physicaldownlink control channel (PDCCH), a MTC PDCCH (MPDCCH), or a narrowbandPDCCH (NPDCCH) (addressing a paging message for NB-IoT).

In a P-RNTI transmitted through an MPDCCH, PO may indicate a startingsubframe of an MPDCCH repetition. In the case of a P-RNTI transmittedthrough an NPDCCH, when a subframe determined based on a PO is not avalid NB-IoT downlink subframe, the PO may indicate a starting subframeof an NPDCCH repetition. Therefore, a first valid NB-IoT downlinksubframe after the PO is the starting subframe of the NPDCCH repetition.

One paging frame (PF) is one radio frame that may include one or aplurality of paging occasions. When DRX is used, the UE needs to monitoronly one PO per DRX cycle. One paging narrow band (PNB) is one narrowband in which the UE receives a paging message. A PF, a PO and a PNB maybe determined based on DRX parameters provided via system information.

FIG. 39 is a flowchart illustrating an example of performing anidle-mode DRX operation.

Referring to FIG. 39 , a UE may receive idle-mode DRX configurationinformation from a base station through higher-layer signaling (e.g.,system information) (S21).

The UE may determine a paging frame (PF) and a paging occasion (PO) tomonitor a PDCCH in a paging DRX cycle based on the idle-mode DRXconfiguration information (S22). In this case, the DRX cycle may includean on duration and a sleep duration (or opportunity for DRX).

The UE may monitor a PDCCH in the PO of the determined PF (S23). Here,for example, the UE monitors only one subframe (PO) per paging DRXcycle. In addition, when the UE receives a PDCCH scrambled with a P-RNTIin the on duration (that is, when paging is detected), the UE maytransition to a connected mode and may transmit and receive data to andfrom the base station.

FIG. 40 schematically illustrates an example of an idle-mode DRXoperation.

Referring to FIG. 40 , when there is traffic directed to a UE in theRRC_IDLE state (hereinafter, referred to as an idle state), paging tothe UE occurs. The UE may periodically wake up (that is, every (paging)DRX cycle) and may monitor a PDCCH. When there is no paging, the UE maytransition to the connected state, may receive data, and may enter thesleep mode again if data does not exist.

<Connected-Mode DRX (C-DRX)>

C-DRX refers to DRX applied in the RRC connected state. The DRX cycle ofC-DRX may include a short DRX cycle and/or a long DRX cycle. Here, theshort DRX cycle may be optional.

When C-DRX is configured, a UE may perform PDCCH monitoring for an onduration. When a PDCCH is successfully detected during the PDCCHmonitoring, the UE may operate (or run) an inactivity timer and maymaintain an awake state. However, when the PDCCH is not successfullydetected during the PDCCH monitoring, the UE may enter a sleep stateafter the on duration expires.

When C-DRX is configured, a PDCCH reception occasion (e.g., a slothaving a PDCCH search space) may be discontinuously configured based onthe C-DRX configuration. However, when C-DRX is not configured, a PDCCHreception occasion (e.g., a slot having a PDCCH search space) can becontinuously configured in the present disclosure.

PDCCH monitoring may be limited to a time period set as a measurementgap regardless of a C-DRX configuration.

FIG. 41 is a flowchart illustrating an example of a method forperforming a C-DRX operation.

A UE may receive RRC signaling (e.g., MAC-MainConfig IE) including DRXconfiguration information from a base station (S31).

The DRX configuration information may include the following information.

-   -   onDurationTimer: Number of PDCCH subframes that can be        continuously monitored at the beginning of a DRX cycle    -   drx-InactivityTimer: Number of PDCCH subframes that can be        continuously monitored when a UE decodes a PDCCH having        scheduling information    -   drx-RetransmissionTimer: Number of PDCCH subframes to be        continuously monitored when HARQ retransmission is expected    -   longDRX-Cycle: Period of on-duration    -   drxStartOffset: Subframe number where a DRX cycle starts    -   drxShortCycleTimer: Number of short DRX cycle    -   shortDRX-Cycle: DRX cycle operating as many as        drxShortCycleTimer when Drx-InactivityTimer expires

Further, when DRX ‘ON’ is set through a DRX command of a MAC commandelement (CE) (S32), the UE monitors a PDCCH for an on duration of theDRX cycle based on the DRX configuration (S33).

FIG. 42 schematically illustrates an example of a C-DRX operation.

When a UE receives scheduling information (e.g., a DL grant) in theRRC_CONNECTED state (hereinafter, referred to as a connected state), theUE may run a DRX inactivity timer and an RRC inactivity timer.

When the DRX inactivity timer expires, a DRX mode may start. The UEwakes up in a DRX cycle and may monitor a PDCCH for a predetermined time(on a duration timer).

In this case, if short DRX is configured, when the UE starts the DRXmode, the UE first starts with a short DRX cycle, and then starts with along DRX cycle after the short DRX cycle expires. Here, the long DRXcycle may correspond to a multiple of the short DRX cycle. In the shortDRX cycle, the UE may more frequently wake up. After the RRC inactivitytimer expires, the UE may transition to the idle state and may performan idle-mode DRX operation.

<IA/RA+DRX Operation>

FIG. 43 schematically illustrates an example of power consumptionaccording to the state of a UE.

Referring to FIG. 43 , after the UE is powered on, the UE performs abootup procedure for loading an application, an initial access/randomaccess procedure for downlink and uplink synchronization with a basestation, and a registration procedure with a network. Here, currentconsumption (or power consumption) in each procedure is shown in FIG. 42.

When the transmission power of the UE is high, the current consumptionof the UE may increase. Further, when there is no traffic to be receivedby the UE or no traffic to be transmitted to the base station, the UEtransitions to the idle mode to reduce power consumption and performs anidle-mode DRX operation.

When paging (e.g., a call) occurs during the idle-mode DRX operation,the UE may transition from the idle mode to the connected mode through acell establishment procedure and may transmit and receive data to andfrom the base station.

When there is no data received from the base station or transmitted tothe base station for a specified time in the connected mode or at a settime, the UE may perform a connected-mode DRX (C-DRX).

When extended DRX (eDRX) is configured for the UE through higher-layersignaling (e.g., system information), the UE may perform an eDRXoperation in the idle mode or the connected mode.

What is claimed is:
 1. A method of performing a hybrid automatic repeatrequest (HARD) process by a user equipment (UE) in a wirelesscommunication system, the method comprising: receiving first informationrelated to a first duration after a configured grant transmission of aphysical uplink shared channel (PUSCH); receiving second informationrelated to a second duration between the configured grant transmissionof the PUSCH and a reception of downlink feedback information (DFI)including HARQ-ACK(acknowledgement) information for the PUSCH; receivinga higher layer signal informing of resources which can be used fortransmitting the PUSCH; transmitting the PUSCH through a first resourceamong the resources without receiving an uplink grant for the PUSCH;monitoring the DFI including the HARQ-ACK information in a secondresource located after the second duration from the first resource; andbased on the HARQ-ACK information not being received within the firstduration from the first resource, retransmitting the PUSCH, wherein thefirst duration is determined based on a configured subcarrier spacing.2. The method of claim 1, wherein the first duration is given in slotunits.
 3. The method of claim 1, wherein the first information isconfigured for an unlicensed band.
 4. The method of claim 1, furthercomprising: performing a listen before talk (LBT) procedure beforetransmitting the PUSCH.
 5. The method of claim 4, wherein the LBTprocedure is a procedure according to which transmissions are notperformed if the channel is identified as being occupied.
 6. The methodof claim 1, further comprising: performing a listen before talk (LBT)procedure before retransmitting the PUSCH.
 7. A user equipment (UE), theUE comprising: a transceiver; and a processor, operably coupled to thetransceiver, wherein the processor is configured to: receive firstinformation related to a first duration after a configured granttransmission of a physical uplink shared channel (PUSCH); receive secondinformation related to a second duration between the configured granttransmission of the PUSCH and a reception of downlink feedbackinformation (DFI) including HARQ-ACK(acknowledgement) information forthe PUSCH; receive a higher layer signal informing of resources whichcan be used for transmitting the PUSCH; transmit the PUSCH through afirst resource among the resources without receiving an uplink grant forthe PUSCH; monitor the DFI including the HARQ-ACK information for thePUSCH in a second resource located after the second duration from thefirst resource; and based on the HARQ-ACK information not being receivedwithin the first duration from the first resource, retransmit the PUSCH,wherein the first duration is determined based on a configuredsubcarrier spacing.
 8. The UE of claim 7, wherein the first duration isgiven in slot units.
 9. The UE of claim 7, wherein the first informationis configured for an unlicensed band.
 10. The UE of claim 7, wherein theprocessor is further configured to: perform a listen before talk (LBT)procedure before transmitting the PUSCH.
 11. The UE of claim 10, whereinthe LBT procedure is a procedure according to which transmissions arenot performed if the channel is identified as being occupied.
 12. The UEof claim 7, wherein the processor is further configured to: perform alisten before talk (LBT) procedure before retransmitting the PUSCH. 13.A method of operating a base station (BS) in a wireless communicationsystem, the method comprising: transmitting, to a user equipment (UE),first information related to a first duration after a configured granttransmission of a physical uplink shared channel (PUSCH) of the UE;transmitting, to the UE, second information related to a second durationbetween the configured grant transmission of the PUSCH and a receptionof downlink feedback information (DFI) includingHARQ-ACK(acknowledgement) information for the PUSCH of the UE;transmitting, to the UE, a higher layer signal informing of resourceswhich can be used for transmitting the PUSCH of the UE; receiving, fromthe UE, the PUSCH through a first resource among the resources withouttransmitting an uplink grant for the PUSCH to the UE; and transmitting,to the UE, the DFI including the HARQ-ACK information for the PUSCH in asecond resource located after the second duration from the firstresource; and, based on the HARQ-ACK information not being received bythe UE within the first duration from the first resource, receiving,from the UE, a retransmission of the PUSCH, wherein the first durationis determined based on a configured subcarrier spacing.
 14. The methodof claim 13, wherein the first duration is given in slot units.
 15. Themethod of claim 13, wherein the first information is configured for anunlicensed band.
 16. The method of claim 13, further comprising:performing a listen before talk (LBT) procedure before transmitting thePUSCH.
 17. The method of claim 16, wherein the LBT procedure is aprocedure according to which transmissions are not performed if thechannel is identified as being occupied.
 18. The method of claim 13,further comprising: performing a listen before talk (LBT) procedurebefore retransmitting the PUSCH.